A164335 Quintic recurrence sequence a(0) = 1, a(n) = n*a(n-1)^5.

1, 1, 2, 96, 32614907904, 184523119031305377426211669050277696887837070322565120

Offset: 0

Author

David Willingham (D.Willingham(AT)wmin.ac.uk), Aug 13 2009

Keywords

• nonn

Comments

Number of different orderings for n-input trees in a Free Quinary Decision Diagram.

a(7) onward have more than 1000 digits. - G. C. Greubel, Sep 14 2017

Links

• G. C. Greubel, Table of n, a(n) for n = 0..6

Crossrefs

Quintic extension of A052129, A123851 and A164334.

Programs

Mathematica

nxt[{n_, a_}] := {n + 1, (n + 1) a^5}; NestList[nxt, {0, 1}, 5][[All, 2]] (* G. C. Greubel, Sep 14 2017 *)

PARI

a(n) = if (n==0, 1, n*a(n-1)^5); \\ Michel Marcus, Sep 14 2017

Formula

a(0) = 1, a(n) = n*a(n-1)^5.