OFFSET
0,4
COMMENTS
See A369134 for comments.
FORMULA
a(n) / A369135(n) = Bernoulli(2*n).
MATHEMATICA
A368846[n_, k_] := If[k == 0, Boole[n == 0], (-1)^(n + k) 2 Binomial[2 k - 1, n] Binomial[2 n + 1, 2 k]];
Map[Total[# LCM @@ Denominator[#]]&, MapIndexed[(-1)^First[#2] Take[#, First[#2]]&, Inverse[PadRight[Table[A368846[n, k], {n, 0, 20}, {k, 0, n}]]]]] (* Paolo Xausa, Jan 16 2024 *)
CROSSREFS
KEYWORD
sign
AUTHOR
Peter Luschny, Jan 14 2024
STATUS
approved