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%I #13 Jan 11 2017 18:21:40
%S 1,21,179,938,3612,11242,29947,70855,152720,305330,573812,1023939,
%T 1748545,2875153,4574922,7073018,10660515,15707931,22680505,32155320,
%U 44840378,61595732,83456781,111659833,147670042,193211824,250301858,321284777,408871655,516181395
%N Number of magic labelings with magic sum n of 7th graph shown in link.
%H Colin Barker, <a href="/A244875/b244875.txt">Table of n, a(n) for n = 0..1000</a>
%H N. J. A. Sloane, <a href="/A244869/a244869.jpg">Graphs for A244869-A244876.</a>
%H R. P. Stanley, <a href="/A002721/a002721.pdf">Examples of Magic Labelings</a>, Unpublished Notes, 1973 [Cached copy, with permission]
%H <a href="/index/Rec#order_09">Index entries for linear recurrences with constant coefficients</a>, signature (7,-20,28,-14,-14,28,-20,7,-1).
%F G.f.: (1 + 14*x + 52*x^2 + 77*x^3 + 52*x^4 + 14*x^5 + x^6) / ((1 - x)^8*(1 + x)).
%F a(n) = (315*(255+(-1)^n) + 306144*n + 498456*n^2 + 452312*n^3 + 250530*n^4 + 86576*n^5 + 17724*n^6 + 1688*n^7) / 80640. - _Colin Barker_, Jan 11 2017
%o (PARI) Vec((1 + 14*x + 52*x^2 + 77*x^3 + 52*x^4 + 14*x^5 + x^6) / ((1 - x)^8*(1 + x)) + O(x^40)) \\ _Colin Barker_, Jan 11 2017
%Y Cf. A244869, A244870, A244871, A244872, A244873, A244874, A244876.
%K nonn,easy
%O 0,2
%A _N. J. A. Sloane_, Jul 08 2014
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