[go: up one dir, main page]

login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

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