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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
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
Sequence in context: A229592 A046710 A251303 * A253292 A253162 A185774
KEYWORD
nonn
AUTHOR
R. J. Mathar, Oct 07 2011
STATUS
approved