July 2018 - Challenge

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This month's challenge is based on a riddle I heard from Odelia Moshe Ostrovsky (thanks!).

Let's call a triplet of natural numbers "obscure" if one cannot uniquely deduce them from their sum and product. For example, {2,8,9} is an obscure triplet, because {3,4,12} shares the same sum (19) and the same product (144).

Find a triplet of ages {a,b,c} that is obscure and stays obscure for three more years: {a+1,b+1,c+1}, {a+2,b+2,c+2} and {a+3,b+3,c+3}.




Update 2/7:

  1. Note that we are asking for three *more* years, i.e. four consecutive years.
  2. To get a bonus '*', find a triplet which stays obscure for at least five more years.


We will post the names of those who submit a correct, original solution! If you don't want your name posted then please include such a statement in your submission!

We invite visitors to our website to submit an elegant solution. Send your submission to the ponder@il.ibm.com.

If you have any problems you think we might enjoy, please send them in. All replies should be sent to: ponder@il.ibm.com

Challenge: 27/06/2018 @ 12:00 PM EST
Solution: 02/08/2018 @ 12:00 PM EST
List Updated: 01/08/2018 @ 12:00 PM EST

People who answered correctly:

Steven Langerwerf (27/06/18 04:01 PM IDT)
Daniëlle van den Berg (27/06/18 04:31 PM IDT)
Guillaume Escamocher (27/06/18 04:57 PM IDT)
Davin Choo (27/06/18 05:25 PM IDT)
Paolo Farinelli (27/06/18 05:41 PM IDT)
Francisco Couzo (27/06/18 06:11 PM IDT)
Daniel Chong Jyh Tar (27/06/18 06:46 PM IDT)
Rickard Björklund (27/06/18 07:23 PM IDT)
Bert Dobbelaere (27/06/18 19:26 IDT)
Nguyen Khac Tung (27/06/18 07:49 PM IDT)
*David F.H. Dunkley (27/06/18 07:52 PM IDT)
Mark Mammel (27/06/18 09:46 PM IDT)
*Uoti Urpala (27/06/18 09:47 PM IDT)
Muralidhar Seshadri (27/06/18 09:53 PM IDT)
*Alper Halbutogullari (27/06/18 10:04 PM IDT)
Alex Fleischer (27/06/18 10:42 PM IDT)
Nir Lavee & Omer Shechter (27/06/18 11:17 PM IDT)
Joaquim Neves Carrapa (27/06/18 11:24 PM IDT)
Susan Brommer (28/06/18 12:09 AM IDT)
*Dieter Beckerle (28/06/18 12:15 AM IDT)
*Noam Lasry (28/06/18 02:23 AM IDT)
*Phil Muhm (28/06/18 06:26 AM IDT)
Eric Loh (28/06/18 07:56 AM IDT)
*Li Li (28/06/18 08:54 AM IDT)
Alistair Ong (28/06/18 09:17 AM IDT)
Loukas Sidiropoulos (28/06/18 10:28 AM IDT)
Jiao Zi-Nan (28/06/18 10:35 AM IDT)
Félix Breton (28/06/18 11:35 AM IDT)
Graham Hemsley (28/06/18 01:44 PM IDT)
Robson Moon (28/06/18 07:05 PM IDT)
Todd Will (28/06/18 07:47 PM IDT)
Kang Jin Cho (28/06/18 07:51 PM IDT)
Franciraldo Cavalcante (28/06/18 08:37 PM IDT)
Vladimir M. Milovanović (28/06/18 09:19 PM IDT)
JJ Rabeyrin (28/06/18 10:57 PM IDT)
Almog Yair (28/06/18 11:19 PM IDT)
*David Greer (29/06/18 00:50 AM IDT)
Jesse Rearick (29/06/18 02:29 AM IDT)
*Igor Karp (29/06/18 04:15 AM IDT)
Erik Hostens (29/06/18 12:43 PM IDT)
Andreas Eisele (29/06/18 12:44 PM IDT)
*Oleg Vlasii (29/06/18 01:37 PM IDT)
Mykola Zubach (29/06/18 03:03 PM IDT)
Jean Buff (29/06/18 03:40 PM IDT)
Susanne Wienand (29/06/18 03:53 PM IDT)
Eden Saig (29/06/18 04:50 PM IDT)
Maurits van altvorst (29/06/18 08:01 PM IDT)
*Andreas Stiller (29/06/18 09:42 PM IDT)
Daniel Bitin (29/06/18 09:55 PM IDT)
Clive Tong (29/06/18 10:47 PM IDT)
Francis Golding (30/06/18 12:31 AM IDT)
*Arthur Vause (30/06/18 01:26 AM IDT)
Hanlin Ren (30/06/18 06:06 AM IDT)
*Sean Egan (30/06/18 07:15 AM IDT)
Joaquim Neves Carrapa (30/06/18 10:13 AM IDT)
*Parth Trivedi (30/06/18 11:04 AM IDT)
Mathias Schenker (30/06/18 11:05 AM IDT)
Dominik Reichl (30/06/18 06:50 PM IDT)
*Andreas Knüpfer (30/06/18 07:05 PM IDT)
Keith Schneider (30/06/18 09:48 PM IDT)
Florian Fischer (30/06/18 10:28 PM IDT)
Rick Kaye (30/06/18 10:55 PM IDT)
Reiner Martin (01/07/18 01:22 AM IDT)
Gary M. Gerken (01/07/18 01:47 AM IDT)
Utkarsh Upadhyay (01/07/18 01:48 AM IDT)
Siddhartha Srivastava (01/07/18 02:48 AM IDT)
James Dow Allen (01/07/18 09:22 AM IDT)
*Victor Chang (01/07/18 09:31 AM IDT)
Rashid Naimi (01/07/18 10:37 AM IDT)
Harald Bögeholz (01/07/18 12:42 PM IDT)
Vivek Nema (01/07/18 12:43 PM IDT)
Bradley Alexander (01/07/18 01:16 PM IDT)
Greg Janée (01/07/18 04:28 PM IDT)
John Snyder (01/07/18 08:32 PM IDT)
Oleg Selin (01/07/18 08:40 PM IDT)
Calvin Pozderac (02/07/18 12:05 AM IDT)
David Brewster (02/07/18 02:19 AM IDT)
Tariq Ramlall (02/07/18 02:27 AM IDT)
Jonathan Martin (02/07/18 02:52 AM IDT)
Jordan Rinder (02/07/18 03:38 AM IDT)
Prashant Wankhede (02/07/18 07:38 AM IDT)
Amos Guler (02/07/18 10:37 AM IDT)
Yasodhar Patnaik (02/07/18 10:39 AM IDT)
Anna Judith (02/07/18 10:58 AM IDT)
*Thomas Egense (02/07/18 12:36 PM IDT)
Paul Shaw (02/07/18 01:48 PM IDT)
Amritpal Singh (02/07/18 02:06 PM IDT)
Robert Lang (02/07/18 03:23 PM IDT)
*Dominik Reichl (02/07/18 04:40 PM IDT)
Joseph DeVincentis (02/07/18 05:05 PM IDT)
Oleg Selin (02/07/18 05:37 PM IDT)
*Tariq Ramlall (02/07/18 06:00 PM IDT)
*Keith Schneider (02/07/18 06:03 PM IDT)
Joaquim Neves Carrapa (02/07/18 09:25 PM IDT)
*Franciraldo Cavalcante (03/07/18 12:42 AM IDT)
Rashid Naimi (03/07/18 04:46 AM IDT)
Darren Tan (03/07/18 07:26 AM IDT)
Sanandan Swaminathan (03/07/18 07:33 AM IDT)
*Emir Haleva (03/07/18 09:34 AM IDT)
Walter Sebastian Gisler (03/07/18 02:17 PM IDT)
Ma Hongqiang (03/07/18 02:55 PM IDT)
Gabriel Maia (03/07/18 02:58 PM IDT)
Rogerio Ponce da Silva (03/07/18 03:34 PM IDT)
Nigel Brumpton (03/07/18 06:27 PM IDT)
*Bert Dobbelaere (03/07/18 06:46 PM IDT)
*Harald Bögeholz (04/07/18 02:47 PM IDT)
Andrzej Bartoszewicz (04/07/18 03:48 PM IDT)
Rudy Cortembert (04/07/18 05:10 PM IDT)
*Alexander Raß (04/07/18 07:13 PM IDT)
Michael Adda (04/07/18 09:06 PM IDT)
Carl Shan (05/07/18 01:13 AM IDT)
Shirish Chinchalkar (05/07/18 03:44 AM IDT)
Kaifei Chen (05/07/18 05:58 AM IDT)
Kenneth Meehan (05/07/18 08:05 AM IDT)
*Dan Ignatoff (05/07/18 09:03 AM IDT)
*Aviv Nisgav (05/07/18 11:28 AM IDT)
*Almog Wald (05/07/18 12:28 PM IDT)
*Oscar Volpatti (05/07/18 02:53 PM IDT)
Rustam Salikhov (05/07/18 02:55 PM IDT)
Fabio Filatrella (05/07/18 04:12 PM IDT)
*Jimmy Waters (05/07/18 05:50 PM IDT)
*Danny Antonetti (05/07/18 06:29 PM IDT)
Jason Plein (05/07/18 07:08 PM IDT)
*Jess Thrysoee (05/07/18 08:22 PM IDT)
Tamir Ganor & Shouky Dan (06/07/18 12:12 AM IDT)
Kebbaj Mohamed reda (06/07/18 03:04 AM IDT)
*Eugene Nonko (06/07/18 04:29 AM IDT)
Marcelo De Barros (06/07/18 10:10 AM IDT)
*David Stevens (06/07/18 12:17 PM IDT)
Marcelo De Barros (06/07/18 04:58 PM IDT)
Michael Liepelt (06/07/18 05:03 PM IDT)
Hao Zheng (06/07/18 06:38 PM IDT)
Feyzullah Egriboyun (06/07/18 07:35 PM IDT)
*Kang Jin Cho (07/07/18 07:57 AM IDT)
*Allen Zhu (07/07/18 09:00 AM IDT)
*Anonymous (07/07/18 11:24 AM IDT)
Noam Zaks (07/07/18 02:39 PM IDT)
*Ethan Watkins (08/07/18 04:21 AM IDT)
Raine Virta (08/07/18 11:09 AM IDT)
Christian Pfaffenzeller (09/07/18 01:52 AM IDT)
Yue Ru Sun (09/07/18 08:18 AM IDT)
Boris Rakús (09/07/18 05:35 PM IDT)
Ed Hall (09/07/18 06:31 PM IDT)
David Friedman (10/07/18 05:39 AM IDT)
Jordan Venderley (10/07/18 05:41 AM IDT)
*Vladimir Volevich (10/07/18 11:24 AM IDT)
Yasodhar (Pattu) Patnaik (10/07/18 02:22 PM IDT)
Adam Kozdroń (10/07/18 02:44 PM IDT)
Kurt Foster (10/07/18 04:26 PM IDT)
Bryce Fore (11/07/18 12:38 AM IDT)
Brian Pietsch (11/07/18 03:46 PM IDT)
Marcel Caria (11/07/18 07:08 PM IDT)
Peter Gerritson (11/07/18 11:39 PM IDT)
*Pi-Ching Liu (12/07/18 05:50 AM IDT)
*Dario Serino (12/07/18 09:55 AM IDT)
*Oren Zeitlin (13/07/18 08:12 AM IDT)
*Motty Porat (13/07/18 03:26 PM IDT)
*Tim Lewis (13/07/18 04:01 PM IDT)
*Florian Fischer (14/07/18 10:10 AM IDT)
*Gil Citro (14/07/18 10:22 PM IDT)
Yongxing Jim Wang (15/07/18 12:52 AM IDT)
Fabio Michele Negroni (15/07/18 08:30 PM IDT)
Stijn Theunis (16/07/18 03:51 PM IDT)
Rajesh Sathiyanarayanan (16/07/18 07:58 PM IDT)
Charles Joscelyne (17/07/18 01:12 PM IDT)
Robert Burns (17/07/18 06:20 PM IDT)
*Thomas Huet (17/07/18 10:05 PM IDT)
Robert Burns (18/07/18 08:12 AM IDT)
*Armin Krauß (18/07/18 02:20 PM IDT)
Andrejs Pilka (18/07/18 05:55 PM IDT)
*Andrei Tsygankov (19/07/18 01:26 AM IDT)
Claudio Hüni (19/07/18 10:20 PM IDT)
*Tom Sirgedas (20/07/18 01:00 AM IDT)
Joseph Berman (20/07/18 08:40 PM IDT)
Rainer Rosenthal (20/07/18 10:40 PM IDT)
*Louis Faucon (21/07/18 12:04 AM IDT)
Raymond Lo (21/07/18 09:31 AM IDT)
Lawrence Hon (21/07/18 04:58 PM IDT)
Lakshman Inkulu (22/07/18 02:49 PM IDT)
Nikky Nikhil (22/07/18 02:55 PM IDT)
Ian Sleightholme (22/07/18 08:39 PM IDT)
David Vainapel (23/07/18 03:38 PM IDT)
Deepak Bal and Paul McKenney (23/07/18 04:25 PM IDT)
Liubing Yu (24/07/18 09:10 AM IDT)
Evert van Dijken (24/07/18 04:17 PM IDT)
Adrian Neacsu (25/07/18 01:31 AM IDT)
Ritesh Ranjan (25/07/18 04:09 PM IDT)
Albert Stadler (25/07/18 10:17 PM IDT)
Benjamin Laufer (26/07/18 07:36 AM IDT)
Gumpina Rama Krishna Chaitanya (26/07/18 10:30 AM IDT)
Tinguaro Barreno (26/07/18 03:08 PM IDT)
Bharatkumar Aryasomayajula (27/07/18 11:57 AM IDT)
Alan Mc Carthy (29/07/18 02:25 PM IDT)
Jörg Binder (29/07/18 05:30 PM IDT)
Michel Le (30/07/18 09:54 AM IDT)
Sasi teja Alluri (30/07/18 01:00 PM IDT)
Datti Sai Kishore (30/07/18 01:01 PM IDT)
Yuval Nezri (30/07/18 02:06 PM IDT)
Wilder Boyden (30/07/18 06:34 PM IDT)
Sergey Koposov (30/07/18 10:14 PM IDT)
Kai Guttmann (30/07/18 10:29 PM IDT)
Sri Mallikarjun J (31/07/18 06:23 PM IDT)
*Hugo Pfoertner (31/07/18 08:42 PM IDT)
Itsik Horovitz (01/08/18 12:17 AM IDT)
Radu-Alexandru Todor (01/08/18 02:26 AM IDT)