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A191999
Denominators of partial products of a Hardy-Littlewood constant.
3
1, 2, 8, 16, 160, 640, 2048, 12288, 24576, 32768, 327680, 786432, 10485760, 62914560, 125829120, 167772160, 9730785280, 583847116800, 3503082700800, 245215789056000
OFFSET
1,2
COMMENTS
See A191998.
FORMULA
a(n) = denominator(r(n)) with
r(n):=product(1-Chi_2(4;p(j))/(p(j)-1),j=1..n), n>=1, with the primes p(j)=A000040(j) and the nontrivial Dirichlet Character modulo 4, called here Chi_2(4;k) = A056594(k).
EXAMPLE
The rationals r(n) are: 1, 3/2, 9/8, 21/16, 231/160, 847/640, 2541/2048, ...
CROSSREFS
KEYWORD
nonn,easy,frac
AUTHOR
Wolfdieter Lang, Jun 21 2011
STATUS
approved