Returning soon
Infinite Search Space hosted recreational maths and programming contests in 2011 and 2012: hard puzzles that ran for months, were scored to the last digit, and were played mostly for bragging rights. It's coming back, with new contests, and a classic room where the old records can finally be beaten.
On two occasions I have been asked, “Pray, Mr. Babbage, if you put into the machine wrong figures, will the right answers come out?” … I am not able rightly to apprehend the kind of confusion of ideas that could provoke such a question.
For many of us, Al Zimmermann's contests are the gold standard: one beautiful problem, months to chip away at it, a leaderboard that counts every improvement, and results that still turn up in the OEIS. ISS was built in their image. Its founder learned the craft on Al's problems, finishing 10th in Retaining Water. ISS's very first About page thanked Al, and it still does.
James J. Youlton Jr's contest site, home to Primal Rings, Tribal Primes, Pyramid Power, King Walking, God's Dice and more. ISS's founder entered every one and helped James put the contests together, and the two sites have always cheered each other on. James is a friend, and a big part of why ISS exists.
See the contests → Read the full history →
Plant N trees on whole-number points to make as many rows of exactly four as possible.
WinnerIl Brigante Pennastorta
Clear 25 boards of coloured tiles for the highest possible score.
WinnerWes Sampson
Colour the largest grid you can, with up to 21 colours, so no rectangle has four corners alike.
WinnerAlex Chernov
A prime-number puzzle that ended in a dead heat at the top.
Joint winnersDmitry Kamenetsky & Alex Chernov
