A376061 a(n) is the denominator of the sum S(n) defined in A376060.

2, 6, 78, 30498, 13021822554, 7121850230383271305026, 6695139092929353602428277531338786356808914258

Offset

0,1

Links

Table of n, a(n) for n=0..6.

Formula

a(n+1) = Catalan(n+1)*a(n)^2 + a(n), with a(0) = 2.

Example

The first few values of S(n) are 1/2, 5/6, 77/78, 30497/30498, 13021822553/13021822554, ...

Mathematica

RecurrenceTable[{a[n+1] == CatalanNumber[n+1]*a[n]^2 + a[n], a[0] == 2}, a, {n, 0, 6}] (* Amiram Eldar, Sep 15 2024 *)

Crossrefs

Cf. A000108, A374663, A375516, A375531, A375532, A375781, A375522, A376048-A376060.

Sequence in context: A136306 A274825 A376059 * A076146 A114552 A302343

Adjacent sequences: A376058 A376059 A376060 * A376062 A376063 A376064

Keyword

nonn,base,frac

Author

N. J. A. Sloane, Sep 14 2024

Status

approved