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A065401
Number of normal play partisan games born on or before day n.
9
1, 4, 22, 1474
OFFSET
0,2
COMMENTS
Fraser and Wolfe prove upper and lower bounds on a(n+1) in terms of a(n). In particular they give the (probably quite weak) lower bound of 3*10^12 for a(4). - Christopher E. Thompson, Aug 06 2015
REFERENCES
Dan Calistrate, Marc Paulhus and David Wolfe, On the lattice structure of finite games, in More Games of No Chance (Berkeley, CA, 2000), Math. Sci. Res. Inst. Publ., 42, Cambridge Univ. Press, Cambridge, 2002, pp. 25-30.
J. H. Conway, On Numbers and Games, Academic Press, NY, 1976.
Aaron N. Siegel, Combinatorial Game Theory, AMS Graduate Texts in Mathematics Vol 146 (2013), p. 158.
LINKS
William E. Fraser and David Wolfe, Counting the number of games, Theoret. Comput. Sci. 313 (2004), pp. 527-532.
FORMULA
a(n) = A125990(2*A114561(n)). - Antti Karttunen, Oct 18 2018
KEYWORD
nonn,hard,more
AUTHOR
R. K. Guy, Nov 23 2001
EXTENSIONS
Dean Hickerson and Robert Li found a(3) in 1974.
STATUS
approved