A038766 Triangle giving number of unbranched catapolytetragons, read by rows.

1, 1, 1, 1, 1, 1, 1, 3, 3, 2, 1, 3, 9, 7, 4, 1, 5, 16, 29, 23, 10, 1, 5, 27, 62, 99, 69, 25, 1, 7, 39, 132, 275, 351, 229, 70, 1, 7, 55, 221, 643, 1121, 1249, 731, 196, 1, 9, 72, 367, 1278, 2997, 4584, 4437, 2385, 574, 1, 9, 93, 540, 2322, 6678, 13458, 18012, 15597, 7657, 1681

Offset

0,8

References

S. J. Cyvin et al., Unbranched catacondensed polygonal systems containing hexagons and tetragons, Croatica Chem. Acta, 69 (1996), 757-774.

Links

Table of n, a(n) for n=0..65.

Example

1; 1,1; 1,1,1; 1,3,3,2; 1,3,9,7,4; ...

Crossrefs

Last diagonal is A001998.

LCM's of all cycles: A060113.

Sequence in context: A186144 A090544 A283755 * A080993 A377787 A140259

Adjacent sequences: A038763 A038764 A038765 * A038767 A038768 A038769

Keyword

nonn,easy,tabl

Author

N. J. A. Sloane, May 03 2000

Status

approved