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%I #9 Jan 16 2019 18:39:51
%S 1,2,24,720,4480,3628800,68428800,118609920,20922789888000,
%T 6402373705728000,115852476579840000,1124000727777607680000,
%U 1909072005333044428800,1148978521728221184000000,12195533784468554420060160000,53050571962438211727261696000000,7973661725263440308097515520000000
%N Denominators of the sequence c(n) satisfying Sum_{k=0..n} c(k)/(n+k+1) = 0 with c(0)=1.
%H Alexander Kalmynin, Petr Kosenko, <a href="https://arxiv.org/abs/1901.04044">Orthorecursive expansion of unity</a>, arXiv:1901.04044 [math.NT], 2019.
%e The sequence c(n) begins: 1, -3/2, 5/24, 77/720, 277/4480, 140173/3628800, ...
%o (PARI) lista(nn) = {my(c0 = 1, vc = vector(nn)); for (n=1, nn, vc[n] = -(2*n+1)*(c0/(n+1) + sum(k=1, n-1, vc[k]/(n+k+1)));); apply(x->numerator(x), concat([c0], vc));}
%Y Cf. A323490 (numerators).
%K nonn,frac
%O 0,2
%A _Michel Marcus_, Jan 16 2019
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