A134762 a(n) = 3*A000984(n) - 2.

1, 4, 16, 58, 208, 754, 2770, 10294, 38608, 145858, 554266, 2116294, 8112466, 31201798, 120349798, 465352558, 1803241168, 7000818658, 27225405898, 106035791398, 413539586458, 1614773623318, 6312296891158, 24700292182798, 96742811049298, 379231819313254

Offset

0,2

Comments

Second inverse binomial transform of the sequence = A134763, (same as A134762 but with interpolated two's).

Links

Table of n, a(n) for n=0..25.

Formula

G.f.: 3/sqrt(1-4*x) - 2/(1-x). - Sergei N. Gladkovskii, Nov 21 2013

Example

a(2) = 16 = 3*A000984(2) - 2 = 3*6 - 2.

Prog

(PARI) a(n) = 3*binomial(2*n, n) - 2; \\ Michel Marcus, Nov 22 2013

Crossrefs

Cf. A000984, A134762.

Sequence in context: A180143 A224128 A123893 * A207276 A047123 A297096

Adjacent sequences: A134759 A134760 A134761 * A134763 A134764 A134765

Keyword

nonn

Author

Gary W. Adamson, Nov 09 2007

Extensions

More terms from Michel Marcus, Nov 22 2013

Status

approved