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A008598
Multiples of 16.
27
0, 16, 32, 48, 64, 80, 96, 112, 128, 144, 160, 176, 192, 208, 224, 240, 256, 272, 288, 304, 320, 336, 352, 368, 384, 400, 416, 432, 448, 464, 480, 496, 512, 528, 544, 560, 576, 592, 608, 624, 640, 656, 672, 688, 704, 720, 736, 752, 768, 784, 800, 816, 832
OFFSET
0,2
COMMENTS
If X is an n-set and Y_i (i=1,2,3,4) mutually disjoint 2-subsets of X then a(n-6) is equal to the number of 5-subsets of X intersecting each Y_i (i=1,2,3,4). - Milan Janjic, Aug 26 2007
LINKS
Tanya Khovanova, Recursive Sequences
Luis Manuel Rivera, Integer sequences and k-commuting permutations, arXiv preprint arXiv:1406.3081 [math.CO], 2014-2015.
FORMULA
a(n) = Sum_{k=1..8n} (i^k+1)*(i^(8n-k)+1), where i=sqrt(-1). - Bruno Berselli, Mar 19 2012
G.f.: 16*x/(x-1)^2. - Vincenzo Librandi, Jun 10 2013
a(n) = A014641(n) - A185212(n). - Leo Tavares, May 24 2022
MAPLE
A008598:=n->16*n; seq(A008598(n), n=0..100); # Wesley Ivan Hurt, Nov 13 2013
MATHEMATICA
Range[0, 1000, 16] (* Vladimir Joseph Stephan Orlovsky, May 31 2011 *)
CoefficientList[Series[16 x / (x - 1)^2, {x, 0, 60}], x] (* Vincenzo Librandi Jun 10 2013 *)
PROG
(PARI) a(n)=16*n \\ Charles R Greathouse IV, Sep 24 2015
CROSSREFS
KEYWORD
nonn,easy
STATUS
approved