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%I #10 Jan 21 2019 20:07:54
%S 10384593717069655257060992658440191,
%T 2854495385411919762116571938898990272765493247,
%U 182687704666362864775460604089535377456991567871
%N Mersenne composites A065341 with 4 or more prime factors.
%p A135386 := proc(n) local i;
%p i := 2^(ithprime(n))-1:
%p if (nops(numtheory[factorset](i)) > 3) then
%p RETURN (i)
%p fi: end: seq(A135386(n), n=1..37); # _Jani Melik_, Feb 09 2011
%t k = {}; Do[If[ ! PrimeQ[2^Prime[n] - 1], c = FactorInteger[2^Prime[n] - 1]; d = Length[c]; If[d >3, AppendTo[k, 2^Prime[n] - 1]]], {n, 1, 40}]; k
%Y Subsequence of A065341.
%Y Cf. A000225, A054723, A134852, A135975, A135976, A135977, A135979.
%K nonn,bref
%O 1,1
%A _Artur Jasinski_, Dec 09 2007
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