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A220836
Triangle read by rows giving coefficients of Zhang-Zhang polynomial for benzenoidal system S(n).
0
1, 1, 2, 1, 4, 4, 1, 6, 13, 9, 1, 8, 26, 38, 20, 1, 10, 43, 96, 106, 45, 1, 12, 64, 190, 321, 284, 101, 1, 14, 89, 328, 742, 1006, 742, 227, 1, 16, 118, 518, 1460, 2660, 3006, 1900, 510
OFFSET
1,3
LINKS
FORMULA
Chou and Witek give a g.f.
EXAMPLE
Triangle begins:
1
1 2
1 4 4
1 6 13 9
1 8 26 38 20
1 10 43 96 106 45
1 12 64 190 321 284 101
1 14 89 328 742 1006 742 227
1 16 118 518 1460 2660 3006 1900 510
...
CROSSREFS
Right hand diagonal is A052534.
Sequence in context: A303872 A013609 A154558 * A008572 A209150 A209145
KEYWORD
nonn,tabl
AUTHOR
N. J. A. Sloane, Dec 23 2012
STATUS
approved