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%I #11 Feb 15 2022 02:46:44
%S 1,4,36,900,75,3675,14700,1778700,300600300,150300150,450900450,
%T 130310230050,47041993048050,47041993048050,94083986096100,
%U 49770428644836900,12442607161209225,10464232622576958225,41856930490307832900,40224510201185827416900
%N Denominators of convergents to 6/Pi^2 based on 1/Zeta(s) = Sum_{k>=1} (mu(k)/k^s).
%D John Derbyshire, "Prime Obsession", Joseph Henry Press, 2003, p. 249.
%F Partial sums of convergents to 6/Pi^2 = 1/Zeta(2) = Sum_{k>=1} (mu(k)/k^2) = 1 - 1/2^2 - 1/3^2 - 1/5^2 + 1/6^2 ...
%e First few convergents to 6/Pi^2 are: 1/1, 3/4, 23/36, 539/900, 47/75, 2228/3675, 9059/14700, ...
%t Denominator @ Accumulate[DeleteCases[Table[MoebiusMu[k]/k^2, {k, 1, 40}], 0]] (* _Amiram Eldar_, Feb 26 2020 *)
%Y Cf. A013661, A055615 (n*mu(n)), A059956, A127900 (numerators of convergents).
%K nonn,frac
%O 1,2
%A _Gary W. Adamson_, Feb 04 2007
%E More terms from _Amiram Eldar_, Feb 26 2020