OFFSET
2,2
LINKS
G. C. Greubel, Table of n, a(n) for n = 2..1000
Index entries for linear recurrences with constant coefficients, signature (5,-10,10,-5,1).
FORMULA
From Ralf Stephan, Feb 07 2004: (Start)
G.f.: x^2*(1 - x + x^2 + x^3 - x^4)/(1-x)^5.
Differences of A027967. (End)
From G. C. Greubel, Jun 30 2019: (Start)
a(n) = (n^4 + 2*n^3 - 25*n^2 + 94*n - 96)/24.
E.g.f.: (96 +24*x - (96 - 72*x + 12*x^2 - 8*x^3 - x^4)*exp(x))/24. (End)
MATHEMATICA
LinearRecurrence[{5, -10, 10, -5, 1}, {1, 4, 11, 26, 54}, 50] (* G. C. Greubel, Jun 30 2019 *)
PROG
(PARI) vector(50, n, n++; (n^4+2*n^3-25*n^2+94*n-96)/24) \\ G. C. Greubel, Jun 30 2019
(Magma) [(n^4+2*n^3-25*n^2+94*n-96)/24: n in [2..50]]; // G. C. Greubel, Jun 30 2019
(Sage) [(n^4+2*n^3-25*n^2+94*n-96)/24 for n in (2..50)] # G. C. Greubel, Jun 30 2019
(GAP) List([2..50], n-> (n^4+2*n^3-25*n^2+94*n-96)/24) # G. C. Greubel, Jun 30 2019
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
EXTENSIONS
Terms a(31) onward added by G. C. Greubel, Jun 30 2019
STATUS
approved