A015623 Quadruples of different integers from [ 1,n ] with no common factors between pairs.

0, 0, 0, 0, 2, 2, 10, 14, 24, 26, 68, 72, 151, 167, 192, 228, 411, 431, 708, 758, 858, 928, 1419, 1475, 1874, 2013, 2353, 2499, 3515, 3571, 4856, 5254, 5747, 6089, 6795, 6979, 9129, 9630, 10437, 10800, 13768, 13978, 17500, 18275, 19210, 20114, 24734

Offset

1,5

Links

Alois P. Heinz, Table of n, a(n) for n = 1..1000

Crossrefs

Partial sums of A185348, Column 4 of triangle A186974.

Sequence in context: A066966 A132443 A048153 * A164124 A003609 A366131

Adjacent sequences: A015620 A015621 A015622 * A015624 A015625 A015626

Keyword

nonn

Author

Olivier Gérard

Status

approved