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%I #18 Aug 05 2022 20:03:12
%S 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,
%T 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,
%U 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
%N Prime factor <= other prime factor of n-th semiprime.
%C Lesser of the prime factors of A001358(n). - _Jianing Song_, Aug 05 2022
%H Zak Seidov, <a href="/A084126/b084126.txt">Table of n, a(n) for n = 1..1000</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Semiprime.html">Semiprime</a>
%F a(n) = A020639(A001358(n)).
%F a(n) = A001358(n)/A006530(A001358(n)). [corrected by _Michel Marcus_, Jul 18 2020]
%F a(n) = A001358(n)/A084127(n).
%t FactorInteger[#][[1,1]]&/@Select[Range[500],PrimeOmega[#]==2&] (* _Harvey P. Dale_, Jun 25 2018 *)
%o (Haskell)
%o a084126 = a020639 . a001358 -- _Reinhard Zumkeller_, Nov 25 2012
%Y Cf. A001358 (the semiprimes), A084127 (greater of the prime factors of the semiprimes).
%Y Cf. A068318, A087718, A087794, A089994, A089995, A096916, A106550, A106554, A108541, A131284, A138510, A138511.
%K nonn
%O 1,1
%A _Reinhard Zumkeller_, May 15 2003
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