A220087 a(n) = 2^n - 27.

-26, -25, -23, -19, -11, 5, 37, 101, 229, 485, 997, 2021, 4069, 8165, 16357, 32741, 65509, 131045, 262117, 524261, 1048549, 2097125, 4194277, 8388581, 16777189, 33554405, 67108837, 134217701, 268435429, 536870885, 1073741797, 2147483621, 4294967269

Offset

0,1

Links

Table of n, a(n) for n=0..32.

Index entries for linear recurrences with constant coefficients, signature (3,-2).

Formula

From Chai Wah Wu, Jan 17 2020: (Start)

a(n) = 3*a(n-1) - 2*a(n-2) for n > 1.

G.f.: (53*x - 26)/((x - 1)*(2*x - 1)). (End)

From Elmo R. Oliveira, Nov 08 2023: (Start)

a(n) = 2*a(n-1) + 27 with a(0) = -26.

E.g.f.: exp(2*x) - 27*exp(x). (End)

Mathematica

Table[2^n - 27, {n, 0, 40}] (* T. D. Noe, Dec 04 2012 *)
LinearRecurrence[{3, -2}, {-26, -25}, 40] (* Harvey P. Dale, May 17 2018 *)

Crossrefs

Cf. A000225, A036563, A185346.

Sequence in context: A205322 A291470 A093538 * A022982 A023468 A261309

Adjacent sequences: A220084 A220085 A220086 * A220088 A220089 A220090

Keyword

sign

Author

Andreas Rieber, Dec 04 2012

Status

approved