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%I #11 Mar 30 2012 17:40:29
%S 26747,26791,26799,26935,611287,611319,611327,611335,611383,620107,
%T 620119,620219,620859,620899,638291,638311,638351,638647,638659,
%U 638671,638691,638779,639071,652003,652027,652187,652551,652583,652603,652735,652751,653047,653059,653063,653071,653095,653119,653215
%N Semiprimes at which the Chebyshev bias of semiprimes == 3 (mod 4) and == 1 (mod 4) becomes positive.
%C There is the sequence SemiprimePi for semiprimes ==1 (mod 4) which grows as 0, 0, 1, 1, 1, 1, 2, 2, 3, 3, 4, 4, 4, 4, 4, 4, 5, 5, 5, 6, 6, 6, 7, 8, 8, 9, 9, 10, 10,... and another SemiprimePi for == 3 (mod 4) which grows as 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 2, 2, 3, 3, 3, 4, 5, 5,... We watch the difference 0, 0, -1, -1, -1, 0, -1, -1, -2, -2, -3, -3, -2,.. and note the semiprimes where this difference becomes >0.
%H Donovan Johnson, <a href="/A196937/b196937.txt">Table of n, a(n) for n = 1..4960</a> (terms < 2*10^9)
%H K. Ford, J. Sneed, <a href="http://dx.doi.org/10.1080/10586458.2010.10390630">Chebyshev's bias for products of two primes</a>, Exper. Math. 19 (4) (2010) 385-398
%Y Cf. A108181, A080774.
%K nonn
%O 1,1
%A _R. J. Mathar_, Oct 07 2011
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