OFFSET
0,2
REFERENCES
M. O'Keeffe, Coordination sequences for lattices, Zeit. f. Krist., 210 (1995), 905-908.
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..1000
M. O'Keeffe, Coordination sequences for lattices, Zeit. f. Krist., 210 (1995), 905-908.
M. O'Keeffe, Coordination sequences for lattices, Zeit. f. Krist., 210 (1995), 905-908. [Annotated scanned copy]
Index entries for linear recurrences with constant coefficients, signature (4,-6,4,-1).
FORMULA
a(n) = n*(11*n^2 + 7) with n>0, with a(0)=1.
G.f.: 1 + 6*x*(3 + 5*x + 3*x^2)/(1-x)^4. - R. J. Mathar, Sep 04 2011
E.g.f.: 1 + x*(18 + 33*x + 11*x^2)*exp(x). - G. C. Greubel, Nov 09 2019
MAPLE
1, seq(11*k^3+7*k, k=1..45);
MATHEMATICA
CoefficientList[Series[1+6*x*(3+5*x+3*x^2)/(1-x)^4, {x, 0, 45}], x] (* Vincenzo Librandi, Jun 19 2012 *)
LinearRecurrence[{4, -6, 4, -1}, {1, 18, 102, 318, 732}, 45] (* Harvey P. Dale, Apr 27 2017 *)
PROG
(Magma) I:=[1, 18, 102, 318, 732]; [n le 5 select I[n] else 4*Self(n-1) -6*Self(n-2)+4*Self(n-3)-Self(n-4): n in [1..45]]; // Vincenzo Librandi, Jun 19 2012
(PARI) vector(46, n, if(n==1, 1, (n-1)*(7+11*(n-1)^2)) ) \\ G. C. Greubel, Nov 09 2019
(Sage) [1]+[n*(7+11*n^2) for n in (1..45)] # G. C. Greubel, Nov 09 2019
(GAP) Concatenation([1], List([1..45], n-> n*(7+11*n^2) )); # G. C. Greubel, Nov 09 2019
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved