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%I #16 Mar 19 2020 16:35:20
%S 1,352,7869952,1243925143552,722906928498737152,
%T 1118389087843083461066752,3794717805092151129643367268352,
%U 24809622030942586708931326728787197952,284876472796397041595189052788763077537431552,5358281136280777382502986500754127200892786313265152
%N A bisection of A000436.
%F a(n) = | 3^(4*n)*2^(4*n+1)*lerchphi(-1,-4*n,1/3) |. - _Peter Luschny_, Apr 27 2013
%F a(n) = 2^(8*n+1)*3^(4*n)*(zeta(-4*n,1/6)-zeta(-4*n,2/3)), where zeta(a,z) is the generalized Riemann zeta function. - _Peter Luschny_, Mar 11 2015
%p a := n -> 2^(8*n+1)*3^(4*n)*(Zeta(0,-4*n,1/6)-Zeta(0,-4*n,2/3)):
%p seq(a(n), n=0..9); # _Peter Luschny_, Mar 11 2015
%t b[0] = 1; b[n_] := b[n] = (-1)^n (1-Sum[(-1)^i Binomial[2n, 2i] 3^(2n-2i) b[i], {i, 0, n-1}]);
%t a[n_] := b[2n];
%t Table[a[n], {n, 0, 9}] (* _Jean-François Alcover_, Jul 08 2019 *)
%o (Sage)
%o from mpmath import mp, lerchphi
%o mp.dps = 64; mp.pretty = True
%o def A156177(n): return abs(3^(4*n)*2^(4*n+1)*lerchphi(-1,-4*n,1/3))
%o [int(A156177(n)) for n in (0..9)] # _Peter Luschny_, Apr 27 2013
%K nonn
%O 0,2
%A _N. J. A. Sloane_, Nov 07 2009
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