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A337207
a(n) is the minimal number of legal positions in Go played on connected graphs with n nodes.
0
1, 5, 15, 41, 107, 273, 707, 1817, 4617, 11867, 30425, 76857, 197603, 505871, 1275465, 3276563, 8406527, 21165273, 54338627, 139513379, 351447657, 901789811, 2304725075, 5840498937, 14978318243, 38107010435, 97141424265, 248995117523, 630641012147
OFFSET
1,2
COMMENTS
Consider a Go game played on general graphs instead of grids. The position that each group has at least one liberty is called a legal position. 2^(n+1)-3 and 3^n-2^n are respectively the trivial lower bound and upper bound of this sequence. The Mathematics of Go interest group computed this sequence up to n=481.
CROSSREFS
KEYWORD
nonn
AUTHOR
Zhujun Zhang, Aug 19 2020
STATUS
approved