IBM Research Ponder This
http://www.ibm.com/research/
The challenge for January is now posted.Thu, 02 January 2014 10:00:00 ESTen-usJanuary Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/January2014.html
The challenge for January is now postedThu, 02 January 2014 10:00:00 ESTDecember solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/December2013.html
The solution for December is now postedThu, 02 January 2014 9:00:00 ESTDecember Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/December2013.html
The challenge for December is now postedThu, 02 January 2014 9:00:00 ESTOctober solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/October2013.html
The solution for October is now postedTue, 06 November 2013 12:00:00 ESTNovember Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/November2013.html
The challenge for November is now postedTue, 06 November 2013 12:00:00 ESTSeptember solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/September2013.html
The solution for September is now postedTue, 06 November 2013 12:00:00 ESTOctober Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/October2013.html
The challenge for October is now postedTue, 06 November 2013 12:00:00 ESTAugust solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/August2013.html
The solution for August is now postedTue, 06 November 2013 12:00:00 ESTSeptember Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/September2013.html
The challenge for September is now postedTue, 06 November 2013 12:00:00 ESTJuly solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/July2013.html
The solution for July is now postedTue, 06 November 2013 12:00:00 ESTAugust Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/August2013.html
The challenge for August is now postedTue, 06 November 2013 12:00:00 ESTJune solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/June2013.html
The solution for June is now postedTue, 02 July 2013 12:00:00 ESTJuly Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/July2013.html
The challenge for July is now postedTue, 02 July 2013 12:00:00 ESTMay solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/May2013.html
The solution for May is now postedTue, 03 June 2013 12:00:00 ESTJune Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/June2013.html
The challenge for June is now postedFri, 31 May 2013 12:00:00 ESTApril solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/April2013.html
The solution for April is now postedTue, 30 April 2013 12:00:00 ESTMay Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/May2013.html
The challenge for May is now postedTue, 30 April 2013 12:00:00 ESTMarch solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/March2013.html
The solution for March is now postedTue, 30 April 2013 12:00:00 ESTApril Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/April2013.html
The challenge for April is now postedFri, 29 March 2013 12:00:00 ESTFebruary solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/February2013.html
The solution for February is now postedFri, 01 March 2013 12:00:00 ESTMarch Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/March2013.html
The challenge for March is now postedFri, 01 March 2013 12:00:00 ESTJanuary solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/January2013.html
The solution for January is now postedFri, 01 February 2013 12:00:00 ESTFebruary Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/February2013.html
The challenge for February is now postedFri, 01 February 2013 12:00:00 ESTDecember solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/December2012.html
The solution for December is now postedWed, 02 January 2013 12:00:00 ESTJanuary Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/January2013.html
The challenge for January is now postedWed, 02 January 2013 12:00:00 ESTNovember solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/November2012.html
The solution for November is now postedMon, 03 December 2012 12:00:00 ESTDecember Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/December2012.html
The challenge for December is now postedThu, 29 November 2012 12:00:00 ESTOctober solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/October2012.html
The solution for October is now postedThu, 01 November 2012 12:00:00 ESTNovember Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/November2012.html
The challenge for November is now postedWed, 31 October 2012 12:00:00 ESTSeptember solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/September2012.html
The solution for September is now postedMon, 01 October 2012 12:00:00 ESTOctober Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/October2012.html
The challenge for October is now postedFri, 28 September 2012 12:00:00 ESTAugust solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/August2012.html
The solution for August is now postedTue, 04 September 2012 12:00:00 ESTSeptember Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/September2012.html
The challenge for September is now postedTue, 04 September 2012 12:00:00 ESTJuly solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/July2012.html
The solution for July is now postedThu, 31 July 2012 18:00:00 ESTAugust Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/August2012.html
The challenge for August is now postedThu, 31 July 2012 18:00:00 ESTJune solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/June2012.html
The solution for June is now postedMon, 2 July 2012 12:00:00 ESTJuly Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/July2012.html
The challenge for July is now postedThu, 28 Jun 2012 13:00:00 ESTMay solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/May2012.html
The solution for May is now postedFri, 1 June 2012 14:00:00 ESTJune Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/June2012.html
The challenge for June is now postedThu, 31 May 2012 13:00:00 ESTApril solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/April2012.html
The solution for April is now postedTue, 1 May 2012 12:00:00 ESTMay Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/May2012.html
The challenge for May is now postedThu, 26 April 2012 12:00:00 ESTMarch solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/March2012.html
The solution for March is now postedThu, 2 Apr 2012 12:00:00 ESTApril Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/April2012.html
The challenge for April is now postedThu, 30 Mar 2012 12:00:00 ESTFebruary solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/February2012.html
The solution for February is now postedThu, 1 Mar 2012 12:00:00 ESTMarch Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/March2012.html
The challenge for March is now posted Thu, 1 Mar 2012 12:00:00 ESTJanuary solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/January2012.html
The solution for January is now postedWed, 1 Feb 2012 12:00:00 ESTFebruary Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/February2012.html
The challenge for February is now posted Wed, 1 Feb 2012 12:00:00 ESTDecember solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/December2011.html
The solution for December is now postedThu, 1 Jan 2012 12:00:00 ESTJanuary Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/January2012.html
The challenge for January is now posted Thu, 1 Jan 2012 12:00:00 ESTNovember solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/November2011.html
The solution for November is now postedThu, 1 Dec 2011 12:00:00 ESTDecember Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/December2011.html
The challenge for December is now posted Thu, 1 Dec 2011 12:00:00 ESTOctober solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/October2011.html
The solution for October has been updatedFri, 4 Nov 2011 12:00:00 ESTNovember Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/November2011.html
The challenge for November is now posted Tue, 1 Nov 2011 12:00:00 ESTOctober solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/October2011.html
The solution for October is now postedTue, 1 Nov 2011 12:00:00 ESTOctober Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/October2011.html
The challenge for October is now posted Sat, 1 Oct 2011 11:00:00 ESTSeptember solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/September2011.html
The solution for September is now postedSat, 1 Oct 2011 12:00:00 ESTSeptember Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/September2011.html
The challenge for September is now posted Thu, 1 Sep 2011 12:00:00 ESTAugust solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/August2011.html
the solution for August is now posted Thu, 1 Sep 2011 12:00:00 ESTJuly solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/July2011.html
the solution for July is now posted Thu, 1 Sep 2011 12:00:00 ESTAugust Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/August2011.html
The challenge for August is now posted Fri, 29 Jul 2011 12:00:00 ESTJuly Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/July2011.html
The challenge for July has been updated Fri, 29 Jul 2011 12:00:00 ESTJuly Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/July2011.html
The challenge for July is now postedFri, 1 Jul 2011 12:00:00 ESTJune solution
http://domino.research.ibm.com/comm/wwwr_ponder.nsf/solutions/June2011.html
the solution for June is now posted Wed, 6 Jul 2011 12:00:00 estJune Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/June2011.html
The challenge for June is now posted Wed, 1 Jun 2011 12:00:00 ESTMay Solution
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/Solutions/May2011.html
The solution for May is now posted Wed, 1 Jun 2011 12:00:00 ESTMarch 2010 Solution
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/Solutions/March2010.html
The solution for March 2010 challenge has been updated Wed, 18 May 2011 12:00:00 ESTApril Solution
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/Solutions/April2011.html
The solution for April has been updated Wed, 4 May 2011 12:00:00 ESTMay Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/May2011.html
The challenge for May is now posted Mon, 2 May 2011 12:00:00 ESTApril Solution
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/Solutions/April2011.html
The solution for April is now posted Mon, 2 May 2011 12:00:00 ESTApril Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/April2011.html
The challenge for April is now posted Fri, 1 Apr 2011 12:00:00 ESTMarch Solution
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/Solutions/March2011.html
The solution for March is now posted Fri, 1 Apr 2011 12:00:00 ESTMarch Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/March2011.html
The challenge for March is now posted Tue, 2 Mar 2011 12:00:00 ESTFebruary Solution
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/Solutions/February2011.html
The solution for February is now posted Tue, 1 Mar 2011 12:00:00 ESTFebruary Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/February2011.html
The challenge for February is now posted Tue, 1 Feb 2011 12:00:00 ESTJanuary Solution
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/Solutions/January2011.html
The solution for January is now posted Tue, 1 Feb 2011 12:00:00 ESTJanuary Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/January2010.html
The challenge for January is now posted Tue, 4 Jan 2011 12:00:00 ESTDecember Solution
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/Solutions/December2010.html
The solution for December is now posted Tue, 4 Jan 2011 12:00:00 ESTNovember Solution
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/Solutions/November2010.html
The solution for November is now posted Tue, 4 Jan 2011 12:00:00 ESTDecember Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/December2010.html
The challenge for December is now posted Fri, 3 Dec 2010 14:00:00 ESTNovember Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/November2010.html
The new challenge for November is now postedTue, 2 Nov 2010 12:00:00 ESTOctober Solution
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/Solutions/October2010.html
The solution for October is now posted Tue, 2 Nov 2010 12:00:00 ESTOctober Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/October2010.html
October challenge updatedMon, 4 Oct 2010 11:00:00 ESTOctober Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/October2010.html
October challenge updatedMon, 4 Oct 2010 11:00:00 ESTOctober Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/October2010.html
The new challenge for October is now posted Thu, 30 Sep 2010 14:00:00 ESTSeptember Solution
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/Solutions/September2010.html
The new solution for September is now posted Thu, 30 Sep 2010 11:00:00 ESTSeptember Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/Challenges/September2010.html
The new challenge for September is now posted Wed, 1 Sep 2010 11:00:00 ESTAugust Solution
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/Solutions/August2010.html
The solution for August is now posted Wed, 1 Sep 2010 12:00:00 ESTJuly Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/Challenges/July2010.html
The new challenge for July is now posted Thu, 1 Jul 2010 12:00:00 ESTJune Solution
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/Solutions/June2010.html
The solution for June is now posted Thu, 1 Jul 2010 10:00:00 ESTJune Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/Challenges/June2010.html
The new challenge for June is now posted Tue, 1 Jun 2010 10:00:00 ESTMay Solution
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/Solutions/May2010.html
The solution for May is now posted Tue, 1 Jun 2010 12:00:00 ESTMay Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/Challenges/May2010.html
May challenge updated Mon, 10 May 2010 12:00:00 ESTMay Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/Challenges/May2010.html
May challenge updated Thu, 6 May 2010 11:00:00 ESTMay Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/Challenges/May2010.html
The new challenge for May is now posted Fri, 30 Apr 2010 11:00:00 ESTMarch Solution
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/Solutions/March2010.html
The new solution for March is now posted Thu, 1 Apr 2010 10:00:00 ESTApril Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/April2010.html
The new challenge for April is now posted Tue, 30 Mar 2010 10:00:00 ESTFebruary Solution
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/Solutions/February2010.html
The new solution for February is now posted Mon, 1 Mar 2010 10:00:00 ESTMarch Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/March2010.html
The new challenge for March is now posted Mon, 1 Mar 2010 10:00:00 ESTJanuary Solution
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/Solutions/January2010.html
The new solution for January is now posted Mon, 1 Feb 2010 14:00:00 ESTFebruary Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/February2010.html
The new challenge for February is now posted Fri, 29 Jan 2010 10:00:00 ESTNovember Solution
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/Solutions/November2009.html
The new solution for November is now posted Tue, 1 Dec 2009 10:00:00 ESTDecember Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/December2009.html
The new challenge for December is now posted Mon, 30 Nov 2009 12:00:00 ESTNovember Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/November2009.html
The new challenge for November is now posted Wed, 4 Nov 2009 10:00:00 ESTOctober Challenge - hint
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/October2009.html
New hint posted for the October Ponder This challengeWed, 7 Oct 2009 15:00:00 ESTOctober Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/October2009.html
The new challenge for October is now postedThu, 1 Oct 2009 10:00:00 ESTSeptember Solution
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/Solutions/September2009.html
The solution for September is now postedThu, 1 Oct 2009 10:00:00 ESTSeptember Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/September2009.html
The new challenge for September is now postedMon, 31 Aug 2009 15:00:00 ESTAugust Solution
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/Solutions/August2009.html
The solution for August is now postedMon, 31 Aug 2009 09:00:00 ESTAugust Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/August2009.html
The new challenge for August is now postedMon, 3 Aug 2009 10:00:00 ESTJuly Solution
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/Solutions/July2009.html
The solution for July is now postedMon, 3 Aug 2009 10:00:00 ESTJuly Challenge - hint
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/July2009.html
New hint posted for the July Ponder This challengeWed, 1 Jul 2009 10:00:00 ESTJune Solution
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/Solutions/June2009.html
The solution for June is now postedWed, 1 Jul 2009 12:00:00 ESTJuly Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/July2009.html
The new challenge for July is now postedMon, 29 Jun 2009 14:00:00 ESTJune Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/June2009.html
The new challenge for June is now postedThu, 28 May 2009 10:00:00 ESTMay Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/May2009.html
The new challenge for May is now postedThu, 30 Apr 2009 15:00:00 ESTApril Challenge - hint
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/May2009.html
New hint posted for the April Ponder This challengeWed, 22 Apr 2009 17:00:00 ESTApril Challenge
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/April2009.html
The new challenge for April is now postedWed, 1 Apr 2009 16:00:00 ESTMarch Challenge - hint
http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/May2009.html
New hint posted for the April Ponder This challengeFri, 27 Mar 2009 12:00:00 EST