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%I #15 Jun 17 2017 03:55:05
%S 0,1,17,118,514,1681,4529,10612,22380,43473,79057,136202,224302,
%T 355537,545377,813128,1182520,1682337,2347089,3217726,4342394,5777233,
%U 7587217,9847036,12642020,16069105,20237841,25271442,31307878,38501009,47021761
%N Polynexus numbers of order 7.
%H Bruno Berselli, <a href="/A083200/b083200.txt">Table of n, a(n) for n = 1..1000</a>
%H <a href="/index/Rec#order_07">Index entries for linear recurrences with constant coefficients</a>, signature (7,-21,35,-35,21,-7,1).
%F a(n) = ((n^7-(n-1)^7)-(n^3-(n-1)^3))/120.
%F G.f.: x^2*(1+10*x+20*x^2+10*x^3+x^4)/(1-x)^7. - Bruno Berselli, Feb 13 2012
%t Table[((n^7 - (n - 1)^7) - (n^3 - (n - 1)^3))/120, {n, 31}] (* _Bruno Berselli_, Feb 13 2012 *)
%Y Cf. A079547, A088889-A088894 (similar sequences).
%K nonn,easy
%O 1,3
%A Xavier Acloque, Jun 01 2003
%E More terms from _David Wasserman_, Oct 26 2004
%E Offset changed (according to the formula) from Bruno Berselli, Feb 13 2012