A015628 Quadruples of different integers from [ 2,n ] with no common factors between pairs.

0, 0, 0, 0, 0, 2, 3, 6, 6, 26, 27, 72, 79, 90, 109, 228, 238, 431, 461, 523, 565, 928, 963, 1255, 1349, 1597, 1697, 2499, 2534, 3571, 3878, 4253, 4510, 5056, 5189, 6979, 7369, 8006, 8282, 10800, 10956, 13978, 14607, 15362, 16098, 20114, 20521, 23743

Offset

2,6

Links

Table of n, a(n) for n=2..49.

Crossrefs

Sequence in context: A056430 A089878 A057545 * A060692 A015698 A068587

Adjacent sequences: A015625 A015626 A015627 * A015629 A015630 A015631

Keyword

nonn

Author

Olivier Gérard

Status

approved