A058374 a(1) = 1; a(n+1) = sum{k=1 to n}[a(k)^a(n+1-k)].

1, 1, 2, 4, 8, 18, 60, 656, 332818, 1152921573343542980

Offset

1,3

Comments

The next term (a(11)) has 198 digits. - Harvey P. Dale, Sep 25 2014

Links

Table of n, a(n) for n=1..10.

Example

a(7) = 1^18 + 1^8 + 2^4 + 4^2 + 8^1 + 18^1 = 1 + 1 + 16 + 16 + 8 + 18 = 60.

Mathematica

Nest[Join[#, {Total[#^Reverse[#]]}]&, {1, 1}, 10] (* Harvey P. Dale, Sep 25 2014 *)

Crossrefs

Sequence in context: A116723 A323020 A180206 * A007881 A367441 A293542

Adjacent sequences: A058371 A058372 A058373 * A058375 A058376 A058377

Keyword

easy,nonn

Author

Leroy Quet, Dec 18 2000

Status

approved