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%I #12 Apr 14 2021 10:04:27
%S 3,5,3,7,5,3,5,7,11,3,13,7,3,11,17,7,3,19,13,5,3,11,5,23,3,5,17,13,3,
%T 11,7,19,29,3,31,7,13,3,17,23,5,3,37,5,19,11,3,5,41,3,17,43,29,11,3,
%U 13,23,31,47,19,3,7,11,5,3,13,5,53,3,5,37,7,3,23,29,13,59,17,3,61,41,31,3,43
%N Second prime divisor of numbers that are not powers of primes (A024619).
%H Amiram Eldar, <a href="/A089992/b089992.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A119288(A024619(n)). - _Amiram Eldar_, Apr 12 2021
%t Select[Table[If[Length[(f = FactorInteger[n])] > 1, f[[2, 1]], 1], {n, 1, 150}], # > 1 &]
%o (PARI) f(n) = a=factor(n);v=a[,1];ln=length(v);if(ln>1,return(v[2]));
%o g(m) = for(x=2,m,if(f(x)>0,print1(f(x)",")));
%Y Cf. A024619, A119288, A089993.
%K nonn
%O 1,1
%A _Cino Hilliard_, Jan 14 2004
%E Offset corrected by _Amiram Eldar_, Apr 12 2021