A078590 a(1)=1, a(2)=1, a(n)=(2^a(n-1) + 1)/a(n-2).

1, 1, 3, 9, 171, 332572817028187686275682948600327513806149983112761

Offset

1,3

Comments

Are all terms integers?

Links

Table of n, a(n) for n=1..6.

Mathematica

nxt[{a_, b_}]:={b, (2^b+1)/a}; NestList[nxt, {1, 1}, 5][[All, 1]]//Quiet (* Harvey P. Dale, Dec 08 2017 *)

Crossrefs

Sequence in context: A217638 A101967 A377026 * A358704 A061963 A174603

Adjacent sequences: A078587 A078588 A078589 * A078591 A078592 A078593

Keyword

nonn

Author

Benoit Cloitre, Dec 06 2002

Status

approved