A154589 a(n) = A154570(n) + A154570(n+1).

4, -1, -2, -4, -8, -16, -32, -64, -128, -256, -512, -1024, -2048, -4096, -8192, -16384, -32768, -65536, -131072, -262144, -524288, -1048576, -2097152, -4194304, -8388608, -16777216, -33554432, -67108864, -134217728, -268435456, -536870912, -1073741824, -2147483648

Offset

0,1

Links

Paolo Xausa, Table of n, a(n) for n = 0..1000

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

Formula

G.f.: (4-9*x)/(1-2*x). a(n+1) = -A000079(n). - R. J. Mathar, Feb 25 2009

E.g.f.: 5 + x/(G(0)+1), where G(k) = 2*k - 1 - x/(1 + x/G(k+1)); (continued fraction). - Sergei N. Gladkovskii, Dec 27 2013

a(n) = (9/2)*0^n - 2^(n-1). - Taras Goy, Jan 21 2026

Mathematica

Join[{4}, -2^Range[0, 35]] (* Paolo Xausa, Oct 09 2025 *)

Crossrefs

Cf. A154570.

Sequence in context: A082903 A258770 A225815 * A354104 A188931 A125560

Adjacent sequences: A154586 A154587 A154588 * A154590 A154591 A154592

Keyword

sign,easy

Author

Paul Curtz, Jan 12 2009

Extensions

Edited by N. J. A. Sloane, Jan 14 2009

More terms from Jason Yuen, Oct 09 2025

Status

approved