A139142 This sequence and A139143 are complements. a(1) = 1, A139143(1) = 2, a(n+1) = a(n) + Sum_{k = 1..n} A139143(k).

1, 3, 9, 20, 37, 61, 93, 135, 188, 253, 331, 423, 530, 653, 793, 951, 1128, 1326, 1546, 1789, 2056, 2348, 2666, 3011, 3384, 3786, 4218, 4681, 5176, 5704, 6266, 6863, 7496, 8167, 8877, 9627, 10418, 11251, 12127, 13047, 14012, 15023, 16081, 17187, 18342, 19547

Offset

1,2

Comments

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

Links

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

Rémy Sigrist, PARI program for A139142

Example

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

Prog

(PARI) See Links section.

Crossrefs

Cf. A139143.

Sequence in context: A187409 A037048 A348090 * A225385 A037257 A145068

Adjacent sequences: A139139 A139140 A139141 * A139143 A139144 A139145

Keyword

nonn

Author

Leroy Quet, Apr 10 2008

Extensions

More terms from Rémy Sigrist, Feb 08 2019

Status

approved