A139020 a(n) = sum_{k=1 to n} A139019(k).

1, 3, 8, 19, 32, 49, 128, 211, 33554432, 67108933, 2199023255552, 4397979403333, 9007199254740992, 18010000530080323

Offset

1,2

Comments

By definition, every term is a power of a prime.

For all n >= 1, a(2n) = 2^m for some m >= 0.

The next terms a(14) = 2^1685, a(15) = 2^1686 - 18010000529304693 are too large to be listed here. Max Alekseyev, Oct 14 2012

Links

Table of n, a(n) for n=1..14.

Crossrefs

Cf. A139019, A139022.

Sequence in context: A171308 A113535 A184444 * A147358 A209367 A086167

Adjacent sequences: A139017 A139018 A139019 * A139021 A139022 A139023

Keyword

nonn

Author

Leroy Quet, Apr 06 2008

Extensions

Corrected and extended by M. F. Hasler, Apr 07 2008

a(10)-a(13) from Donovan Johnson, Nov 30 2008

a(14)-a(15) from Max Alekseyev, Oct 14 2012

Status

approved