A133655 a(n) = 2*A016777(n) + A016777(n-1) - (n+1).

1, 7, 15, 23, 31, 39, 47, 55, 63, 71, 79, 87, 95, 103, 111, 119, 127, 135, 143, 151, 159, 167, 175, 183, 191, 199, 207, 215, 223, 231, 239, 247, 255, 263, 271, 279, 287, 295, 303, 311, 319, 327, 335, 343, 351, 359, 367, 375, 383, 391, 399, 407, 415

Offset

0,2

Links

Table of n, a(n) for n=0..52.

Index entries for linear recurrences with constant coefficients, signature (2,-1).

Formula

Equals "1" followed by A004771.

Binomial transform of [1, 6, 2, -2, 2, -2, 2, ...].

G.f.: (2*x^2+5*x+1)/(x-1)^2. - Harvey P. Dale, Sep 13 2011

Example

a(3) = 23 = 2*A016777(3) + A016777(2) - 4 = 2*10 + 7 - 4.
a(3) = 23 = (1, 3, 3, 1) dot (1, 6, 2, -2) = (1, 18, 6, -2).

Mathematica

CoefficientList[Series[(2 x^2+5 x+1)/(x-1)^2, {x, 0, 60}], x] (* Harvey P. Dale, Sep 13 2011 *)

Crossrefs

Cf. A004771, A016777.

Sequence in context: A189754 A059562 A017149 * A004771 A029724 A194400

Adjacent sequences: A133652 A133653 A133654 * A133656 A133657 A133658

Keyword

nonn,easy

Author

Gary W. Adamson, Sep 20 2007

Extensions

More terms and corrected definition from R. J. Mathar, Jun 08 2008

Status

approved