%I #16 Feb 14 2024 02:18:20
%S 97,55117,62169337,78727802257,101638351073377,131638631590149697,
%T 170585384377200633217,221074709452366968135937,
%U 286511970539849391404729857,371319329591314394530363646977,481229811357035602199451623479297
%N a(n) = 6^(4n+2) + 6^(3n+2) + 3 * 6^(2n+1) + 6^(n+1) + 1: the right Aurifeuillian factor of 6^(12n+6) + 1.
%C The corresponding left Aurifeuillian factor is A220981.
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Cunningham_project">Cunningham Project</a>
%H <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (1555,-345210,12427560,-72550080,60466176).
%F Aurifeuillian factorization: 6^(12n+6) + 1 = (6^(4n+2) + 1) * A220981(n) * a(n).
%F G.f.: -(162922752*x^4-124050528*x^3+9947772*x^2-95718*x+97) / ((x-1)*(6*x-1)*(36*x-1)*(216*x-1)*(1296*x-1)). [_Colin Barker_, Jan 03 2013]
%t Table[6^(4n+2) + 6^(3n+2) + 3 * 6^(2n+1) + 6^(n+1) + 1, {n, 0, 20}]
%Y Cf. A092440, A085601, A220978, A198410, A220979-A220990.
%K nonn,easy
%O 0,1
%A _Stuart Clary_, Dec 27 2012
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