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List of primes generated by factoring successive primary pseudoperfect numbers (A054377).
5

%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