A185810 Riordan array ((1+x-sqrt(1-2x-3x^2))/(2x(1-x)),(1+x-sqrt(1-2x-3x^2))).

1, 2, 2, 3, 6, 4, 5, 12, 16, 8, 9, 24, 40, 40, 16, 18, 50, 92, 120, 96, 32, 39, 110, 212, 312, 336, 224, 64, 90, 254, 500, 784, 976, 896, 512, 128

Offset

0,2

Links

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

Vladimir Kruchinin and D. V. Kruchinin, Composita and their properties, arXiv:1103.2582 [math.CO], 2011-2013.

Formula

Riordan array ((1+x-sqrt(1-2x-3x^2))/(2x(1-x)),(1+x-sqrt(1-2x-3x^2))).

Example

[1]
[2,2]
[3,6,4]
[5,12,16,8]
[9,24,40,40,16]
[18,50,92,120,96,32]
[39,110,212,312,336,224,64]
[90,254,500,784,976,896,512,128]

Crossrefs

Sequence in context: A193862 A258631 A254947 * A015050 A284222 A207623

Adjacent sequences: A185807 A185808 A185809 * A185811 A185812 A185813

Keyword

nonn,tabl

Author

Vladimir Kruchinin, Feb 05 2011

Status

approved