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

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

Offset: 0

Author

N. J. A. Sloane, Sep 14 2024

Keywords

• nonn
• base
• frac

Examples

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

Crossrefs

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

Programs

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 *)

Formula

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