A171878 a(n) = a(n-1) + a(n-2)*a(n-3) + a(n-4)^a(n-5), with initial terms 0,0,0,0,1.

0, 0, 0, 0, 1, 2, 3, 6, 13, 33, 120, 765, 4831534, 55040353993453427047, 410186270246002225336426103593500672000000000000055040353997149550557

Offset

0,6

Comments

First 5 terms are {0,0,0,0,1}; thereafter apply the recurrence. Note that 0^0=1.

Links

Table of n, a(n) for n=0..14.

R. Munafo, Accelerating Sequences

Mathematica

nxt[{a_, b_, c_, d_, e_}]:={b, c, d, e, e+d*c+b^a}; Join[{0, 0, 0}, NestList[nxt, {0, 1, 2, 3, 6}, 11][[;; , 1]]] (* Harvey P. Dale, Jun 13 2025 *)

Crossrefs

Sequence in context: A220699 A202086 A227366 * A117403 A002877 A065845

Adjacent sequences: A171875 A171876 A171877 * A171879 A171880 A171881

Keyword

nonn

Author

Robert Munafo, Jan 21 2010

Status

approved