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A317984
Expansion of 140*x*(1 + 4*x + x^2) / (1 - x)^5.
5
140, 1260, 5040, 14000, 31500, 61740, 109760, 181440, 283500, 423500, 609840, 851760, 1159340, 1543500, 2016000, 2589440, 3277260, 4093740, 5054000, 6174000, 7470540, 8961260, 10664640, 12600000, 14787500, 17248140, 20003760, 23077040, 26491500, 30271500
OFFSET
1,1
COMMENTS
Seems to be the fourth column of A316387.
FORMULA
G.f.: 140*x*(1 + 4*x + x^2) / (1 - x)^5.
a(n) = 35*n^4 + 70*n^3 + 35*n^2.
a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5) for n>5.
PROG
(PARI) Vec(140*x*(1 + 4*x + x^2) / (1 - x)^5 + O(x^40))
(PARI) a(n) = 35*n^4 + 70*n^3 + 35*n^2
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Colin Barker, Aug 13 2018
STATUS
approved