a(n) is the denominator of tanh(Sum_{k=1..n-1} artanh(k/n)), where artanh is the inverse hyperbolic tangent function.

A383431

a(n) is the denominator of tanh(Sum_{k=1..n-1} artanh(k/n)), where artanh is the inverse hyperbolic tangent function.

Terms

    a(0) =1a(1) =2a(2) =11a(3) =18a(4) =127a(5) =463a(6) =1717a(7) =3218a(8) =24311a(9) =92379a(10) =352717a(11) =1352079a(12) =5200301a(13) =20058301a(14) =77558761a(15) =150270098a(16) =1166803111a(17) =4537567651a(18) =17672631901a(19) =68923264411a(20) =269128937221

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