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A024143
a(n) = 12^n - n^3.
2
1, 11, 136, 1701, 20672, 248707, 2985768, 35831465, 429981184, 5159779623, 61917363224, 743008369357, 8916100446528, 106993205376875, 1283918464546120, 15407021574582993, 184884258895032320, 2218611106740432079, 26623333280885238072, 319479999370622919989
OFFSET
0,2
FORMULA
From Colin Barker, Oct 11 2018: (Start)
G.f.: (1 - 5*x + 14*x^2 + 43*x^3 + 13*x^4) / ((1 - x)^4*(1 - 12*x)).
a(n) = 16*a(n-1) - 54*a(n-2) + 76*a(n-3) - 49*a(n-4) + 12*a(n-5) for n>4.
(End)
PROG
(Magma) [12^n-n^3: n in [0..20]]; // Vincenzo Librandi, Jul 01 2011
(PARI) a(n)=12^n-n^3 \\ Charles R Greathouse IV, Jul 01 2011
(PARI) Vec((1 - 5*x + 14*x^2 + 43*x^3 + 13*x^4) / ((1 - x)^4*(1 - 12*x)) + O(x^20)) \\ Colin Barker, Oct 11 2018
CROSSREFS
Sequence in context: A336180 A209487 A227101 * A057718 A123800 A233258
KEYWORD
nonn,easy
STATUS
approved