References to A069990

(-1)^(n+1)/5*sum(k=1,2n,C(2n+1,k)*B(k)*5^k) where C(n,k) are the binomial coefficients, B(k) the Bernoulli numbers.
1, 15, 389, 17687, 1230957, 121576879, 16166877205, 2784640846791

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