A113876 a(n) = a(n-1) + 2^(k(n)), where k(n) is the n-th term of the sequence formed by k(1)=0 together with the numbers A042964.

1, 5, 13, 77, 205, 1229, 3277, 19661, 52429, 314573, 838861, 5033165, 13421773, 80530637, 214748365, 1288490189, 3435973837, 20615843021, 54975581389, 329853488333, 879609302221, 5277655813325, 14073748835533, 84442493013197

Offset

1,2

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..300

Index entries for linear recurrences with constant coefficients, signature (1, 16, -16).

Formula

G.f.: (1+x-8*x^2)/(2*(-1+x)*(-1+4*x)*(1+4*x)). - Vaclav Kotesovec, Nov 28 2012

Crossrefs

Cf. A099974, A112627, A080355, A080567, A099969, A099970, A099971.

Sequence in context: A081525 A027612 A027457 * A333082 A214536 A363015

Adjacent sequences: A113873 A113874 A113875 * A113877 A113878 A113879

Keyword

nonn

Author

Artur Jasinski, Jan 27 2006

Extensions

Edited with better definition and offset corrected by Omar E. Pol, Jan 08 2009

Status

approved