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 A084126 Prime factor <= other prime factor of n-th semiprime. 37
 2, 2, 3, 2, 2, 3, 3, 2, 5, 2, 3, 2, 5, 2, 3, 2, 7, 3, 5, 3, 2, 2, 5, 3, 2, 7, 2, 5, 2, 3, 7, 3, 2, 5, 2, 3, 5, 2, 7, 11, 2, 3, 3, 7, 2, 3, 2, 11, 5, 2, 5, 2, 3, 7, 2, 13, 3, 2, 3, 5, 11, 2, 3, 2, 7, 5, 2, 11, 3, 2, 5, 7, 2, 3, 13, 2, 5, 3, 13, 3, 11, 2, 7, 2, 5, 3, 2, 2, 7, 17, 3, 5, 2, 13, 7, 2, 3, 5, 3, 2 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Lesser of the prime factors of A001358(n). - Jianing Song, Aug 05 2022 LINKS Zak Seidov, Table of n, a(n) for n = 1..1000 Eric Weisstein's World of Mathematics, Semiprime FORMULA a(n) = A020639(A001358(n)). a(n) = A001358(n)/A006530(A001358(n)). [corrected by Michel Marcus, Jul 18 2020] a(n) = A001358(n)/A084127(n). MATHEMATICA FactorInteger[#][[1, 1]]&/@Select[Range[500], PrimeOmega[#]==2&] (* Harvey P. Dale, Jun 25 2018 *) PROG (Haskell) a084126 = a020639 . a001358 -- Reinhard Zumkeller, Nov 25 2012 CROSSREFS Cf. A001358 (the semiprimes), A084127 (greater of the prime factors of the semiprimes). Cf. A068318, A087718, A087794, A089994, A089995, A096916, A106550, A106554, A108541, A131284, A138510, A138511. Sequence in context: A273458 A159953 A074595 * A136032 A135975 A334796 Adjacent sequences: A084123 A084124 A084125 * A084127 A084128 A084129 KEYWORD nonn AUTHOR Reinhard Zumkeller, May 15 2003 STATUS approved

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Last modified February 21 04:30 EST 2024. Contains 370219 sequences. (Running on oeis4.)