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A137193
Number of n-celled polyhexes with perimeter < 4n+2.
0
0, 0, 1, 2, 10, 46, 215, 1037, 5083, 24918, 122437
OFFSET
1,4
COMMENTS
These are n-cell polyhexes with the perimeter less than the maximum possible one.
If we associate a graph to a polyhex with vertices representing cells and edges representing two cells with a common edge, then this sequence enumerates polyhexes whose corresponding graphs have cycles.
FORMULA
CROSSREFS
Sequence in context: A106709 A204091 A221196 * A006213 A137635 A029706
KEYWORD
hard,more,nonn
AUTHOR
Tanya Khovanova, Mar 03 2008
STATUS
approved