A335751 a(n) = denominator(Bernoulli(2*n)*(1/2 - n)! / sqrt(Pi)).
2, 6, 15, 63, 225, 693, 1289925, 4455, 34459425, 808782975, 5685805125, 4106936925, 18767808934875, 72977109975, 491292329653125, 305714614450620375, 1578522255175490625, 33864491287501875, 6076788748684677645496875, 34996278233163121875, 55478375013295336399171875
Offset: 0
Examples
r(n) = 1/2, 1/6, 1/15, 2/63, 4/225, 8/693, 11056/1289925, 32/4455, ...
Programs
-
Maple
a := n -> bernoulli(2*n)*(1/2 - n)! / sqrt(Pi): seq(denom(simplify(a(n))), n = 0..21);
Formula
a(n) = denominator(-2*n*Zeta(1 - 2*n)*(1/2 - n)! / sqrt(Pi)) for n >= 1.