%I #17 Apr 19 2014 17:23:22
%S 44745755,1812338107,9266824499,12308871853,13657352875,22767480811,
%T 22930161667,24068927659,25549554505,25770503549,57939582163,
%U 90219135299,90329609821,96949951147,103126759951
%N A subset of numbers n such that n^4 is a Sierpinski number.
%C A sequence constructed from Izotov's trick.
%C If n belongs to this sequence and n does not end in 5, then n^4 has the covering set {3, 5, 17, 97, 241, 257, 673}.
%H Anatoly S. Izotov, <a href="http://www.fq.math.ca/Scanned/33-3/izotov.pdf">A note on Sierpinski numbers</a>
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Sierpinski_number">Sierpinski number</a>
%t (* even if nn is increased, no additional terms are generated *) nn = 14; lst = {}; n = 44745755; p = 2^12; m = 3*(p^4 - 1)/(p - 1); Do[a = n + (-1)^c*m; n = a/GCD[a, p]; AppendTo[lst, Abs@n], {c, 0, nn}]; Union@lst
%Y Subset of A233469. Cf. A076336.
%K nonn,easy,fini,full
%O 1,1
%A _Arkadiusz Wesolowski_, Jun 09 2012
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