OFFSET
0,2
LINKS
Colin Barker, Table of n, a(n) for n = 0..1000
Peter John Hilton and Jean Pedersen, Descartes, Euler, Poincaré, Pólya and Polyhedra, L'Enseign. Math., 27 (1981), 327-343. See Cor. 2.
Index entries for linear recurrences with constant coefficients, signature (4,-6,4,-1).
FORMULA
From Colin Barker, Aug 15 2016: (Start)
a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4) for n>3.
G.f.: -4*x*(1-2*x-x^2) / (1-x)^4. (End)
E.g.f.: 4*x*(-3 + x^2)*exp(x)/3. - G. C. Greubel, Apr 28 2019
MATHEMATICA
LinearRecurrence[{4, -6, 4, -1}, {0, -4, -8, -4}, 50] (* G. C. Greubel, Apr 28 2019 *)
PROG
(PARI) concat(0, Vec(-4*x*(1-2*x-x^2)/(1-x)^4 + O(x^50))) \\ Colin Barker, Aug 15 2016
(Magma) [4*n*(n^2-3*n-1)/3: n in [0..50]]; // G. C. Greubel, Apr 28 2019
(Sage) [4*n*(n^2-3*n-1)/3 for n in (0..50)] # G. C. Greubel, Apr 28 2019
(GAP) List([0..50], n-> 4*n*(n^2-3*n-1)/3) # G. C. Greubel, Apr 28 2019
CROSSREFS
KEYWORD
sign,easy
AUTHOR
N. J. A. Sloane, Aug 14 2016
STATUS
approved