1,2

A139143 consists of all positive integers not in A139142 and vice versa.

Rémy Sigrist, Table of n, a(n) for n = 1..10000

Rémy Sigrist, PARI program for A139142

A specific example: a(5) = a(4) + Sum_{k = 1..4} A139143(k) = 20 + 2 + 4 + 5 + 6 = 37.

(PARI) See Links section.

Cf. A139143.

Sequence in context: A174866 A187409 A037048 * A225385 A037257 A145068

Adjacent sequences: A139139 A139140 A139141 * A139143 A139144 A139145

nonn

Leroy Quet, Apr 10 2008

More terms from Rémy Sigrist, Feb 08 2019

approved