OFFSET
1,2
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..1000
J. H. Conway and N. J. A. Sloane, Low-Dimensional Lattices VII: Coordination Sequences, Proc. Royal Soc. London, A453 (1997), 2369-2389 (pdf).
G. Nebe and N. J. A. Sloane, Home page for this lattice
Index entries for linear recurrences with constant coefficients, signature (9,-36,84,-126,126,-84,36,-9,1).
FORMULA
G.f.: -x*(x^8 + 232*x^7 + 7228*x^6 + 55384*x^5 + 133510*x^4 + 107224*x^3 + 24508*x^2 + 232*x + 1)/(x - 1)^9. - Colin Barker, Oct 29 2012
MAPLE
a:= n-> 57/7*n^8-108/7*n^7+30*n^6-72*n^5+39*n^4-36*n^3+300/7*n^2+24/7*n+1:
seq (a(n), n=1..30);
MATHEMATICA
CoefficientList[Series[-(x^8 + 232 x^7 + 7228 x^6 + 55384 x^5 + 133510 x^4 + 107224 x^3 + 24508 x^2 + 232 x + 1)/(x - 1)^9, {x, 0, 40}], x] (* Vincenzo Librandi, Oct 13 2013 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved