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A024142
12^n-n^2.
2
1, 11, 140, 1719, 20720, 248807, 2985948, 35831759, 429981632, 5159780271, 61917364124, 743008370567, 8916100448112, 106993205378903, 1283918464548668, 15407021574586143, 184884258895036160
OFFSET
0,2
FORMULA
G.f.: (1-4*x+14*x^2+11*x^3)/((1-12*x)*(1-x)^3). - Vincenzo Librandi, Oct 06 2014
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 *)
PROG
(Magma) [12^n-n^2: n in [0..20]]; // Vincenzo Librandi, Jul 01 2011
(PARI) a(n)=12^n-n^2 \\ Charles R Greathouse IV, Jul 01 2011
CROSSREFS
Cf. similar sequences listed in A024025.
Sequence in context: A174289 A003378 A142930 * A024296 A324084 A141907
KEYWORD
nonn,easy
AUTHOR
STATUS
approved