A133546 Binomial transform of [1,3,5,6,7,8,9,10,11,...] (i.e., positive integers except 2 and 4).

1, 4, 12, 31, 74, 169, 376, 823, 1782, 3829, 8180, 17395, 36850, 77809, 163824, 344047, 720878, 1507309, 3145708, 6553579, 13631466, 28311529, 58720232, 121634791, 251658214, 520093669, 1073741796, 2214592483, 4563402722

Offset

1,2

Comments

Row sums of triangle A133545.

Links

Table of n, a(n) for n=1..29.

Index entries for linear recurrences with constant coefficients, signature (6,-13,12,-4).

Formula

G.f.: x*((1-2*x+x^2-x^3)/((x-1)^2*(2*x-1)^2)).

Example

a(3) = 12 = sum of row 3 terms of triangle A133545: (6+5+1).
a(4) = 31 = (1,3,3,1) dot (1,3,5,6) = (1+9+15+6).

Crossrefs

Cf. A133545.

Sequence in context: A129707 A320545 A232580 * A190376 A276785 A171844

Adjacent sequences: A133543 A133544 A133545 * A133547 A133548 A133549

Keyword

nonn,easy

Author

Gary W. Adamson, Sep 15 2007

Extensions

Extended, edited and formula added by Olivier Gérard, Oct 12 2007

Status

approved