A022775 Place where n-th 1 occurs in A007336.

1, 3, 6, 11, 17, 25, 34, 44, 56, 69, 84, 100, 117, 136, 156, 178, 201, 226, 252, 279, 308, 338, 370, 403, 437, 473, 510, 549, 589, 631, 674, 718, 764, 811, 860, 910, 961, 1014, 1068, 1124, 1181, 1239, 1299, 1360, 1423, 1487, 1553, 1620, 1688

Offset: 1

Author

Clark Kimberling

Keywords

• nonn

Crossrefs

Cf. A007336.

Programs

PARI

a(n)=1+sum(k=1,n-1,ceil(sqrt(2)*k)) \\ Benoit Cloitre, Jan 24 2009

Formula

a(n) = 1 + Sum_{k=1..n-1} ceiling(sqrt(2)*k). - Benoit Cloitre, Jan 24 2009