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A309746
Number of ways of placing 2*n-1 nonattacking queens on a hexagonal board with edge-length n in Glinski's hexagonal chess.
4
1, 0, 0, 2, 0, 0, 0, 6, 0, 36, 0, 72, 332, 1596, 6972
OFFSET
1,4
COMMENTS
Conjecture: for n >= 12 is a(n) > 0. Proved for n <= 20. - Vaclav Kotesovec, Sep 06 2019
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Vaclav Kotesovec, Aug 15 2019
EXTENSIONS
a(15) from Vaclav Kotesovec, Aug 28 2019
STATUS
approved