OFFSET
0,2
COMMENTS
Partial sums of A008385.
LINKS
T. D. Noe, Table of n, a(n) for n = 0..1000
J. H. Conway and N. J. A. Sloane, Low-Dimensional Lattices VII: Coordination Sequences, Proc. Royal Soc. London, A453 (1997), 2369-2389 (pdf).
Index entries for linear recurrences with constant coefficients, signature (6,-15,20,-15,6,-1).
FORMULA
a(n) = (2*n+1)*(63*n^4+126*n^3+217*n^2+154*n+60)/60. - T. D. Noe, Apr 29 2007
G.f.: (1+x)*(1+24*x+76*x^2+24*x^3+x^4)/(1-x)^6. - Colin Barker, Mar 16 2012
MATHEMATICA
LinearRecurrence[{6, -15, 20, -15, 6, -1}, {1, 31, 271, 1281, 4251, 11253}, 30] (* Harvey P. Dale, Apr 08 2018 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved