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A081912
a(n) = 6^n*(n^2 - n + 72)/72.
3
1, 6, 37, 234, 1512, 9936, 66096, 443232, 2985984, 20155392, 136048896, 917070336, 6167549952, 41358864384, 276451356672, 1841557856256, 12224809598976, 80871817347072, 533189772509184, 3503818505060352, 22952550207062016
OFFSET
0,2
COMMENTS
Binomial transform of A081911 6th binomial transform of (1,0,1,0,0,0,...). Case k=6 where a(n,k) = k^n*(n^2 - n + 2k^2)/(2k^2) with g.f. (1 - 2kx + (k^2+1)x^2)/(1-kx)^3.
FORMULA
a(n) = 6^n*(n^2 - n + 72)/72.
G.f.: (1 - 12x + 37x^2)/(1-6x)^3.
PROG
(Magma) [6^n*(n^2-n+72)/72: n in [0..40]]; // Vincenzo Librandi, Apr 27 2011
CROSSREFS
Sequence in context: A081570 A122898 A317629 * A081188 A218186 A154623
KEYWORD
easy,nonn
AUTHOR
Paul Barry, Mar 31 2003
STATUS
approved