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 A196937 Semiprimes at which the Chebyshev bias of semiprimes == 3 (mod 4) and == 1 (mod 4) becomes positive. 1
 26747, 26791, 26799, 26935, 611287, 611319, 611327, 611335, 611383, 620107, 620119, 620219, 620859, 620899, 638291, 638311, 638351, 638647, 638659, 638671, 638691, 638779, 639071, 652003, 652027, 652187, 652551, 652583, 652603, 652735, 652751, 653047, 653059, 653063, 653071, 653095, 653119, 653215 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS 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. LINKS Donovan Johnson, Table of n, a(n) for n = 1..4960 (terms < 2*10^9) K. Ford, J. Sneed, Chebyshev's bias for products of two primes, Exper. Math. 19 (4) (2010) 385-398 CROSSREFS Cf. A108181, A080774. Sequence in context: A229592 A046710 A251303 * A253292 A253162 A185774 Adjacent sequences:  A196934 A196935 A196936 * A196938 A196939 A196940 KEYWORD nonn AUTHOR R. J. Mathar, Oct 07 2011 STATUS approved

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Last modified October 18 17:13 EDT 2019. Contains 328186 sequences. (Running on oeis4.)