A120653 Triangle read by rows: numbers of isomers of unbranched a-4-catapolyheptagons.

1, 1, 1, 1, 1, 1, 2, 3, 3, 1, 6, 10, 11, 3, 1, 20, 46, 48, 21, 5, 1, 72, 192, 228, 116, 37, 5, 1, 272, 840, 1080, 692, 254, 55, 7, 1, 1056, 3584, 5112, 3776, 1690, 446, 79, 7, 1, 4160, 15392, 23920, 20216, 10476, 3474, 748, 105, 9, 1, 16512, 65536, 11084, 104448

Offset

0,7

References

J. Brunvoll, S. J. Cyvin and B. N. Cyvin, Isomer enumeration of polygonal systems..., J. Molec. Struct. (Theochem), 364 (1996), 1-13.

Links

Table of n, a(n) for n=0..58.

Example

Triangle begins
1
1 1
1 1 1
2 3 3 1
6 10 11 3 1
20 46 48 21 5 1
72 192 228 116 37 5 1

Crossrefs

Columns give A063376, A121138-A121141.

Sequence in context: A076239 A019798 A214734 * A323850 A236937 A323748

Adjacent sequences: A120650 A120651 A120652 * A120654 A120655 A120656

Keyword

nonn,tabl

Author

N. J. A. Sloane, Aug 18 2006

Status

approved