A176776 a(n) = 2^n-n*(n-2).

1, 3, 4, 5, 8, 17, 40, 93, 208, 449, 944, 1949, 3976, 8049, 16216, 32573, 65312, 130817, 261856, 523965, 1048216, 2096753, 4193864, 8388125, 16776688, 33553857, 67108240, 134217053, 268434728, 536870129, 1073740984, 2147482749

Offset

0,2

Links

Table of n, a(n) for n=0..31.

Index entries for linear recurrences with constant coefficients, signature (5,-9,7,-2).

Formula

G.f.: ( 1-2*x-2*x^2+5*x^3 ) / ( (2*x-1)*(x-1)^3 ). - R. J. Mathar, Feb 18 2016

Mathematica

Table[2^n-n*(n-2), {n, 0, 5!}]

Crossrefs

Cf. A142974.

Sequence in context: A106048 A219038 A258454 * A049931 A335436 A058983

Adjacent sequences: A176773 A176774 A176775 * A176777 A176778 A176779

Keyword

nonn,easy

Author

Vladimir Joseph Stephan Orlovsky, Apr 25 2010

Status

approved