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A015623 Quadruples of different integers from [ 1,n ] with no common factors between pairs. 3
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 (list; graph; refs; listen; history; text; internal format)
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 A307538

Adjacent sequences:  A015620 A015621 A015622 * A015624 A015625 A015626

KEYWORD

nonn

AUTHOR

Olivier Gérard

STATUS

approved

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Last modified April 10 02:39 EDT 2020. Contains 333392 sequences. (Running on oeis4.)