|
%I #11 Jul 13 2013 12:03:38
%S 3,3,3,5,3,3,5,3,3,7,3,5,3,3,5,3,3,7,3,5,3,7,3,5,3,3,3,5,3,7,11,3,5,3,
%T 7,3,3,11,5,3,3,5,3,7,3,13,3,5,3,3,5,11,3,3,3,7,5,3,11,3,5,7,3,13,3,3,
%U 5,3,3,5,13,3,11,3,7,3,5,3,3,5,3,3,7,17,3,5,3,13,7,3,5,3,3,11,3,17,5,3,7,3
%N Smallest prime factor of n-th odd composite integers A071904.
%C Records are for n's such that A071904(n) = squares of primes.
%C a(n) = A020639(A071904(n)). [_Reinhard Zumkeller_, Oct 10 2011]
%H Reinhard Zumkeller, <a href="/A162022/b162022.txt">Table of n, a(n) for n = 1..10000</a>
%e A071904(1)=9, hence a(1)=3, A071904(4)=25, hence a(4)=5.
%t nn=501;With[{ci=Complement[Range[9,nn,2],Prime[Range[PrimePi[nn]]]]}, FactorInteger[ #][[1,1]]&/@ci] (* _Harvey P. Dale_, Nov 30 2012 *)
%Y Cf. A014076, A071904.
%K nonn
%O 1,1
%A _Zak Seidov_, Jun 25 2009
%E Corrected example a(4)=5 Francesco Antoni (francesco_antoni(AT)yahoo.com), Aug 04 2010
|
