A167887 n-th single or isolated number plus n-th non-single or nonisolated number.

2, 5, 9, 17, 25, 31, 39, 47, 53, 60, 67, 75, 83, 89, 98, 103, 110, 119, 126, 133, 139, 154, 159, 167, 181, 189, 196, 201, 208, 216, 230, 237, 251, 264, 271, 277, 285, 297, 305, 312, 320, 328, 334, 347, 362, 368, 374, 389, 396, 409, 415, 422, 431, 438, 445, 451

Offset

1,1

Links

Table of n, a(n) for n=1..56.

Formula

a(n)=A167706(n)+A167707(n).

Example

a(1)=2+0=2, a(2)=4+1=5, a(3)=6+3=9, a(4)=12+5=17.

Crossrefs

Cf. A167706, A167707.

Sequence in context: A036711 A080740 A123324 * A023603 A334087 A308760

Adjacent sequences: A167884 A167885 A167886 * A167888 A167889 A167890

Keyword

nonn

Author

Juri-Stepan Gerasimov, Nov 14 2009

Extensions

All terms > 110 corrected by R. J. Mathar, May 30 2010

Status

approved