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%I #8 Mar 14 2020 18:53:32
%S 2,2,3,2,3,7,2,3,7,43,2,3,11,23,31,2,3,11,23,31,47059,2,3,11,17,101,
%T 149,3109,2,3,11,23,31,47059,2217342227,1729101023519
%N List of primes generated by factoring successive primary pseudoperfect numbers (A054377).
%C It is unknown whether there are infinitely many primary pseudoperfect numbers or any odd ones.
%C See A054377 for other comments, references, links, etc.
%C For prime factors of Giuga numbers, see A236434; of terms in Sylvester's sequence, see A126263.
%e 2 = 2.
%e 6 = 2 * 3.
%e 42 = 2 * 3 * 7.
%e 1806 = 2 * 3 * 7 * 43.
%e 47058 = 2 * 3 * 11 * 23 * 31.
%e 2214502422 = 2 * 3 * 11 * 23 * 31 * 47059.
%e 52495396602 = 2 * 3 * 11 * 17 * 101 * 149 * 3109.
%e 8490421583559688410706771261086 = 2 * 3 * 11 * 23 * 31 * 47059 * 2217342227 * 1729101023519.
%t A054377 = Cases[Import["https://oeis.org/A054377/b054377.txt", "Table"], {_, _}][[All, 2]];
%t First /@ Flatten[FactorInteger[A054377], 1] (* _Robert Price_, Mar 14 2020 *)
%Y Cf. A054377, A126263, A216825, A216826, A236434.
%K nonn,more,hard
%O 1,1
%A _Jonathan Sondow_, Jan 25 2014
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