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%I #6 Jun 13 2015 00:55:37
%S 970,3940,219246804790,205684244417408273530,
%T 11480068853945505053489115880,47065929034956905708053692550,
%U 2626939693541678540279445026253849400,2464437767031050248773603452558570281788774040,137550230606703955058365608367051590003016395627772390
%N Heptagonal numbers (A000566) that are the sum of five consecutive heptagonal numbers.
%H Colin Barker, <a href="/A257975/b257975.txt">Table of n, a(n) for n = 1..160</a>
%H <a href="/index/Rec#order_09">Index entries for linear recurrences with constant coefficients</a>, signature (1,0,0,11981655542024930675232002,-11981655542024930675232002,0,0,-1,1).
%F G.f.: -10*x*(211462*x^8 +198379896430716*x^7 +11072383489254815935515*x^6 +34322119735654912553073*x^5 -14213722750292211889419959*x^4 +20568424419816146874*x^3 +21924680085*x^2 +297*x +97) / ((x -1)*(x^2 -1860498*x +1)*(x^2 +1860498*x +1)*(x^4 +3461452808002*x^2 +1)).
%e 970 is in the sequence because H(20) = 970 = 112 + 148 + 189 + 235 + 286 = H(7)+...+H(11).
%o (PARI) Vec(-10*x*(211462*x^8 +198379896430716*x^7 +11072383489254815935515*x^6 +34322119735654912553073*x^5 -14213722750292211889419959*x^4 +20568424419816146874*x^3 +21924680085*x^2 +297*x +97) / ((x -1)*(x^2 -1860498*x +1)*(x^2 +1860498*x +1)*(x^4 +3461452808002*x^2 +1)) + O(x^20)) \\ _Colin Barker_, May 15 2015
%Y Cf. A000566, A133324, A257954.
%K nonn,easy
%O 1,1
%A _Colin Barker_, May 15 2015
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