A060803 a(n) = Sum_{k=0..n} 2^(2^k).

2, 6, 22, 278, 65814, 4295033110, 18446744078004584726, 340282366920938463481821351509772796182, 115792089237316195423570985008687907853610267032561502502939405359422902436118

Offset

0,1

Comments

Partial sums of A001146.

Number of Boolean functions with up to n arguments. - Paul Tarau (paul.tarau(AT)gmail.com), Jun 06 2008

Links

Harry J. Smith, Table of n, a(n) for n = 0..11

Paul Tarau, Isomorphic Data Encodings and their Generalization to Hylomorphisms on Hereditarily Finite Data Types, 2009.

Formula

a(0) = 2 and a(n) - a(n-1) = 2^2^n, n > 0.

Example

a(3) = 278 because a(3) = 2^2^0 + 2^2^1 + 2^2^2 + 2^2^3 = 2 + 4 + 16 + 256.

Prog

(Haskell) -- code generating the infinite sequence:
scanl (+) 2 (map (\x->2^2^x) [1..]) - Paul Tarau (paul.tarau(AT)gmail.com), Jun 06 2008
(PARI) { for (n=0, 11, write("b060803.txt", n, " ", sum(k=0, n, 2^(2^k))); ) } \\ Harry J. Smith, Jul 12 2009

Crossrefs

Cf. A001146, A001147, A115245.

Sequence in context: A095856 A180367 A111061 * A341884 A213134 A140837

Adjacent sequences: A060800 A060801 A060802 * A060804 A060805 A060806

Keyword

nonn

Author

Varol Akman (akman(AT)cs.bilkent.edu.tr), Apr 28 2001

Extensions

More terms from Benoit Cloitre, May 13 2002

Edited by N. J. A. Sloane, Jun 07 2008

Status

approved