A015635 - OEIS

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A015635

Number of ordered quadruples of integers from [ 1,n ] with no common factors between triples.

1, 3, 9, 18, 43, 62, 125, 181, 282, 370, 597, 725, 1090, 1336, 1709, 2085, 2873, 3280, 4366, 5018, 6054, 6966, 8854, 9790, 11943, 13451, 15744, 17530, 21237, 22839, 27331, 30169, 34186, 37498, 42916, 45948, 53484, 58104, 64699, 69534, 79743

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OFFSET

1,2

LINKS

Table of n, a(n) for n=1..41.

CROSSREFS

Sequence in context: A291143 A057578 A271370 * A062882 A363534 A027101

Adjacent sequences: A015632 A015633 A015634 * A015636 A015637 A015638

KEYWORD

nonn

AUTHOR

Olivier Gérard

STATUS

approved