A024142 12^n-n^2.

1, 11, 140, 1719, 20720, 248807, 2985948, 35831759, 429981632, 5159780271, 61917364124, 743008370567, 8916100448112, 106993205378903, 1283918464548668, 15407021574586143, 184884258895036160

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn
• easy

Links

• Vincenzo Librandi, Table of n, a(n) for n = 0..300
• Index entries for linear recurrences with constant coefficients, signature (15,-39,37,-12).

Crossrefs

Cf. similar sequences listed in A024025.

Programs

Magma

[12^n-n^2: n in [0..20]]; // Vincenzo Librandi, Jul 01 2011

Mathematica

Table[12^n - n^2, {n, 0, 25}] (* or *) CoefficientList[Series[(1 - 4 x + 14 x^2 + 11 x^3)/((1 - 12 x) (1 - x)^3), {x, 0, 30}], x] (* Vincenzo Librandi, Oct 06 2014 *)

PARI

a(n)=12^n-n^2 \\ Charles R Greathouse IV, Jul 01 2011

Formula

G.f.: (1-4*x+14*x^2+11*x^3)/((1-12*x)*(1-x)^3). - Vincenzo Librandi, Oct 06 2014