Search: id:A055213 Results 1-1 of 1 results found. %I A055213 %S A055213 120,6972,261224,7092774,148688232,2503611964,34779531480,406309208481, %T A055213 4048627642976,34778882769216,259669578902016,1695618078654976, %U A055213 9726900031328256,49134911067979776,218511510918189056,852888183557922816 %N A055213 Number of n-piece positions at checkers, for n=1 ... 24. %C A055213 The total number of possible positions is a(1)+...+a(24) = 500995484682338672639. %C A055213 However, not all of these positions are legal, i.e. reachable from the start position. - R. Stephan, Sep 18 2004 %D A055213 Jonathan Schaeffer, N. Burch, Yngvi Bjornsson, Akihiro Kishimoto, Martin Muller, Rob Lake, Paul Lu and Steve Sutphen. "Checkers Is Solved", Science, Vol. 317, September 14, 2007, pp. 1518-1522. %D A055213 Jonathan Schaeffer, Yngvi Bjornsson, N. Burch, Akihiro Kishimoto, Martin Muller, Rob Lake, Paul Lu and Steve Sutphen. Solving Checkers, International Joint Conference on Artificial Intelligence (IJCAI), pp. 292-297, 2005. Distinguished Paper Prize. %H A055213 J. Schaeffer, Table of n, a(n) for n = 1..24 [Taken fron link below] %H A055213 J. Schaeffer, Chinook: Full sequence and more info %H A055213 J. Schaeffer, Chinook: Publications %H A055213 J. Schaeffer and R. Lake, Solving the game of checkers, in: R. Nowakowski (ed.), Games of No Chance (1996), p. 119-133. %H A055213 Yngvi Bjornsson, N. Burch, Rob Lake, Joe Culberson, Paul Lu, Jonathan Schaeffer, Steve Sutphen, Chinook: Total Number of Positions %e A055213 n=1: A red piece can go on any of 28 squares (it can't reside on the last row) and a red king can be on any of 32 squares. Double that to include black, total of 120. %Y A055213 A133803(n) = floor log a(n). %Y A055213 Sequence in context: A061541 A003438 A092710 this_sequence A035190 A035815 A001785 %Y A055213 Adjacent sequences: A055210 A055211 A055212 this_sequence A055214 A055215 A055216 %K A055213 fini,nonn,full %O A055213 1,1 %A A055213 Jud McCranie (j.mccranie(AT)comcast.net), Jun 23 2000 Search completed in 0.001 seconds