OFFSET
0,2
LINKS
Colin Barker, Table of n, a(n) for n = 0..1000
N. J. A. Sloane, Graphs for A244869-A244876.
R. P. Stanley, Examples of Magic Labelings, Unpublished Notes, 1973 [Cached copy, with permission]
Index entries for linear recurrences with constant coefficients, signature (5,-9,5,5,-9,5,-1).
FORMULA
G.f.: (1 + 4*x + 7*x^2 + 4*x^3 + x^4) / ((1 - x)^6*(1 + x)).
From Colin Barker, Jan 11 2017: (Start)
a(n) = (15*(63 + (-1)^n) + 2592*n + 2880*n^2 + 1660*n^3 + 510*n^4 + 68*n^5) / 960.
a(n) = 5*a(n-1) - 9*a(n-2) + 5*a(n-3) + 5*a(n-4) - 9*a(n-5) + 5*a(n-6) - a(n-7) for n>6.
(End)
MATHEMATICA
LinearRecurrence[{5, -9, 5, 5, -9, 5, -1}, {1, 9, 43, 143, 379, 859, 1738}, 50] (* Paolo Xausa, Dec 06 2023 *)
PROG
(PARI) Vec((1+4*x+7*x^2+4*x^3+x^4) / ((1-x)^6*(1+x)) + O(x^40)) \\ Colin Barker, Jan 11 2017
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Jul 08 2014
STATUS
approved