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 A171079 Denominator of s_{2n}, where s_0 = 1/2, s_n = | 2^n*(2^(n-1)-1)*Bernoulli(n)/n! | for n>0. 2

%I

%S 2,3,45,945,4725,13365,638512875,18243225,23260111875,38979295480125,

%T 1531329465290625,274446060013125,201919571963756521875,

%U 11094481976030578125,80664808595725181953125,5660878804669082674070015625,31245110285511170603633203125,75344438393998438430390625

%N Denominator of s_{2n}, where s_0 = 1/2, s_n = | 2^n*(2^(n-1)-1)*Bernoulli(n)/n! | for n>0.

%D F. Hirzebruch, Topological Methods in Algebraic Geometry, Springer, 3rd. ed., 1966; p. 12, Eq. 11.

%F a(n) = denominator(Zeta(2*n)*(4^n-2)/Pi^(2*n)). - _Peter Luschny_, Aug 11 2014

%e 1/2, 1/3, 7/45, 62/945, 127/4725, 146/13365, 2828954/638512875, 32764/18243225, 16931177/23260111875, 11499383114/38979295480125, ...

%p A171079 := n -> denom(Zeta(2*n)*(4^n-2)/Pi^(2*n));

%p seq(A171079(n), n=0..17); # _Peter Luschny_, Aug 11 2014

%Y Cf. A171078 (numerators).

%K nonn,frac

%O 0,1

%A _N. J. A. Sloane_, Sep 06 2010

%E a(0) changed in accordance with the zeta based formula. _Peter Luschny_, Aug 18 2014

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Last modified September 19 18:02 EDT 2020. Contains 337181 sequences. (Running on oeis4.)