A239102 Riordan array read by rows, corresponding to g.f. (1+x*y^3)/((1-x-y)*(1+x*y^3)+x*y^4).

1, 2, 1, 6, 3, 1, 20, 10, 4, 1, 66, 35, 15, 5, 1, 222, 121, 56, 21, 6, 1, 756, 420, 204, 84, 28, 7, 1, 2598, 1464, 736, 323, 120, 36, 8, 1, 8994, 5122, 2643, 1215, 487, 165, 45, 9, 1, 31322, 17983, 9468, 4510, 1912, 706, 220, 55, 10, 1

Offset

0,2

Links

Alois P. Heinz, Rows n = 0..140, flattened

D. Baccherini, D. Merlini, R. Sprugnoli, Binary words excluding a pattern and proper Riordan arrays, Discrete Math. 307 (2007), no. 9-10, 1021--1037. MR2292531 (2008a:05003).

Example

Triangle begins:
1
2 1
6 3 1
20 10 4 1
66 35 15 5 1
222 121 56 21 6 1
756 420 204 84 28 7 1
2598 1464 736 323 120 36 8 1
...

Crossrefs

Sequence in context: A213221 A180281 A187888 * A239103 A246971 A092392

Adjacent sequences: A239099 A239100 A239101 * A239103 A239104 A239105

Keyword

nonn,tabl

Author

N. J. A. Sloane, Mar 25 2014

Extensions

More terms from Alois P. Heinz, Sep 03 2014

Status

approved