

A244871


Number of magic labelings with magic sum n of 3rd graph shown in link.


2



1, 10, 55, 217, 672, 1755, 4030, 8386, 16135, 29140, 49941, 81915, 129430, 198037, 294652, 427780, 607725, 846846, 1159795, 1563805, 2078956, 2728495, 3539130, 4541382, 5769907, 7263880, 9067345, 11229631, 13805730, 16856745, 20450296, 24661000, 29570905
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

0,2


LINKS

Table of n, a(n) for n=0..32.
N. J. A. Sloane, Graphs for A244869A244876.
R. P. Stanley, Examples of Magic Labelings, Unpublished Notes, 1973 [Cached copy, with permission]
Index entries for linear recurrences with constant coefficients, signature (5, 8, 0, 14, 14, 0, 8, 5, 1).


FORMULA

G.f.: (1+5*x+13*x^2+22*x^3+13*x^4+5*x^5+x^6)/((1x)^7*(1+x)^2).
a(n) = n^6/48 + 3*n^5/16 + 77*n^4/96 + 2*n^3 + 37*n^2/12  n*(1)^n/32 + 89*n/32  3*(1)^n/64 + 67/64. [Bruno Berselli, Jul 08 2014]


MATHEMATICA

Table[n^6/48 + 3 n^5/16 + 77 n^4/96 + 2 n^3 + 37 n^2/12  n (1)^n/32 + 89 n/32  3 (1)^n/64 + 67/64, {n, 0, 40}] (* Bruno Berselli, Jul 08 2014 *)


CROSSREFS

Cf. A244869A244876.
Sequence in context: A357730 A341989 A341070 * A162617 A341139 A070212
Adjacent sequences: A244868 A244869 A244870 * A244872 A244873 A244874


KEYWORD

nonn,easy


AUTHOR

N. J. A. Sloane, Jul 08 2014


STATUS

approved



