OFFSET
0,2
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
G.f.: (1+x)*(1+34*x+146*x^2+34*x^3+x^4)/(1-x)^6. [Colin Barker, Mar 16 2012]
MAPLE
18/5*n^5+9*n^4+38/3*n^3+10*n^2+71/15*n+1;
MATHEMATICA
CoefficientList[Series[(1+x)*(1+34*x+146*x^2+34*x^3+x^4)/(1-x)^6, {x, 0, 30}], x] (* or *) LinearRecurrence[{6, -15, 20, -15, 6, -1}, {1, 41, 411, 2051, 6981, 18733}, 30] (* Harvey P. Dale, Sep 03 2016 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved