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%I #10 Feb 05 2016 20:49:11
%S 1,2,4,5,8,10,13,15,16,17,20,25,26,29,30,32,34,35,37,39,40,41,50,51,
%T 52,53,55,58,60,61,64,65,68,70,73,74,75,78,80,82,85,87,89,91,95,97,
%U 100,101,102,104,106,109,110,111,113,115,116,119,120,122,123,125,128,130,136,137,140,143,145,146,148,149,150
%N Numbers having at least the same number of prime factors of the form 4*k+1 than of the form 4*k+3, when counted with multiplicity.
%C Numbers n for which A083025(n) >= A065339(n) or equally, for which A079635(n) >= 0.
%C Closed under multiplication.
%H Antti Karttunen, <a href="/A268381/b268381.txt">Table of n, a(n) for n = 1..10000</a>
%t Position[Array[Map[Length, {Select[#, Mod[#, 4] == 1 &], Select[#, Mod[#, 4] == 3 &]}] &@ Flatten@ Apply[Table[#1, {#2}] &, FactorInteger@ #, 1] &, {150}], {a_, b_} /; a >= b] // Flatten (* _Michael De Vlieger_, Feb 05 2016 *)
%o (Scheme, with _Antti Karttunen_'s IntSeq-library)
%o (define A268381 (MATCHING-POS 1 1 (COMPOSE not negative? A079635)))
%Y Complement: A268380.
%Y Disjoint union of A072202 and A268379.
%Y Cf. A079635, A065339, A083025.
%K nonn
%O 1,2
%A _Antti Karttunen_, Feb 05 2016
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