A003819 a(1)=a(2)=1, a(n+1) = (a(n)^4 +1)/a(n-1).

1, 1, 2, 17, 41761, 178910008847318626, 24533960352822051755918055684179592096697004630540952679692131057

Offset

1,3

Links

Table of n, a(n) for n=1..7.

Maple

A003819 := proc(n) option remember; if n <= 2 then 1 else (A003819(n-1)^4+1)/A003819(n-2); fi; end;

Mathematica

nxt[{a_, b_}]:={b, (b^4+1)/a}; Transpose[NestList[nxt, {1, 1}, 6]][[1]] (* Harvey P. Dale, Jun 21 2015 *)

Crossrefs

Sequence in context: A002814 A122207 A174305 * A078624 A163319 A269836

Adjacent sequences: A003816 A003817 A003818 * A003820 A003821 A003822

Keyword

nonn

Author

Waldemar Pompe (pompe(AT)zodiac1.mimuw.edu.pl)

Status

approved