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%I #6 Aug 15 2013 17:57:16
%S 3,15,27,39,51,63,75,87,91,99,111,123,135,147,159,171,183,195,203,207,
%T 219,231,243,255,259,267,279,291,303,315,327,339,351,363,371,375,387,
%U 399,411,423,427,435,447,459,471,483,495,507,519,531,539,543,555,567
%N Numbers n such that n == 3 modulo (spf(n)+1), where spf(m) is the smallest prime dividing m (A020639).
%C A080063(m) = 3 iff m = a(k) for some k.
%H Harvey P. Dale, <a href="/A080065/b080065.txt">Table of n, a(n) for n = 1..1000</a>
%t Select[Range[600],Mod[#,FactorInteger[#][[1,1]]+1]==3&] (* _Harvey P. Dale_, Aug 15 2013 *)
%Y Cf. A080064.
%K nonn
%O 1,1
%A _Reinhard Zumkeller_, Jan 24 2003