A155083 A directed animal related triangle.

1, 1, 1, 2, 3, 1, 5, 9, 6, 1, 13, 29, 25, 10, 1, 35, 92, 100, 55, 15, 1, 96, 291, 377, 266, 105, 21, 1, 267, 915, 1375, 1169, 602, 182, 28, 1

Offset

0,4

Comments

First column is A005773. Row sums are A129775.

Links

Table of n, a(n) for n=0..35.

Formula

G.f.: 1/(1-xy-x/(1-x-xy-x^2/(1-x-xy-x^2/(1-x-xy-x^2/(1-...))))) (continued fraction).

Example

Triangle begins
1,
1, 1,
2, 3, 1,
5, 9, 6, 1,
13, 29, 25, 10, 1,
35, 92, 100, 55, 15, 1,
96, 291, 377, 266, 105, 21, 1,
267, 915, 1375, 1169, 602, 182, 28, 1

Crossrefs

Sequence in context: A147747 A039599 A154380 * A011357 A080409 A255689

Adjacent sequences: A155080 A155081 A155082 * A155084 A155085 A155086

Keyword

easy,nonn,tabl

Author

Paul Barry, Jan 19 2009

Status

approved