OFFSET
1,1
COMMENTS
Seems to be the negative of the third column of A316387.
LINKS
Colin Barker, Table of n, a(n) for n = 1..1000
Index entries for linear recurrences with constant coefficients, signature (6,-15,20,-15,6,-1).
FORMULA
G.f.: 420*x*(1 + x)*(1 + 10*x + x^2) / (1 - x)^6.
a(n) = 420 * A000538(n).
a(n) = 84*n^5 + 210*n^4 + 140*n^3 - 14*n.
a(n) = 6*a(n-1) - 15*a(n-2) + 20*a(n-3) - 15*a(n-4) + 6*a(n-5) - a(n-6) for n>6.
PROG
(PARI) Vec(420*x*(1 + x)*(1 + 10*x + x^2) / (1 - x)^6 + O(x^40))
(PARI) a(n) = 84*n^5 + 210*n^4 + 140*n^3 - 14*n
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Colin Barker, Aug 13 2018
STATUS
approved