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 A236433 List of primes generated by factoring successive primary pseudoperfect numbers (A054377). 5
 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, 149, 3109, 2, 3, 11, 23, 31, 47059, 2217342227, 1729101023519 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS It is unknown whether there are infinitely many primary pseudoperfect numbers or any odd ones. See A054377 for other comments, references, links, etc. For prime factors of Giuga numbers, see A236434; of terms in Sylvester's sequence, see A126263. LINKS EXAMPLE 2 = 2. 6 = 2 * 3. 42 = 2 * 3 * 7. 1806 = 2 * 3 * 7 * 43. 47058 = 2 *  3 * 11 * 23 * 31. 2214502422 =  2 *  3 * 11 * 23 * 31 * 47059. 52495396602 =  2 * 3 * 11 * 17 * 101 * 149 * 3109. 8490421583559688410706771261086 = 2 *  3 * 11 * 23 * 31 * 47059 * 2217342227 * 1729101023519. MATHEMATICA A054377 = Cases[Import["https://oeis.org/A054377/b054377.txt", "Table"], {_, _}][[All, 2]]; First /@ Flatten[FactorInteger[A054377], 1] (* Robert Price, Mar 14 2020 *) CROSSREFS Cf. A054377, A126263, A216825, A216826, A236434. Sequence in context: A129568 A177892 A341758 * A117122 A122828 A242213 Adjacent sequences:  A236430 A236431 A236432 * A236434 A236435 A236436 KEYWORD nonn,more,hard AUTHOR Jonathan Sondow, Jan 25 2014 STATUS approved

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Last modified September 20 05:37 EDT 2021. Contains 347577 sequences. (Running on oeis4.)