A015646 - OEIS

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A015646

Number of 5-tuples of different integers from [ 1,n ] with no common factors among triples.

0, 0, 0, 0, 1, 3, 15, 28, 69, 111, 259, 336, 671, 906, 1355, 1769, 2961, 3461, 5438, 6501, 8613, 10371, 15022, 16807, 22759, 26512, 33090, 37822, 50603, 54583, 71528, 80768, 96067, 107756, 131271, 141215, 177195, 196173, 227094, 246828

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OFFSET

1,6

LINKS

Table of n, a(n) for n=1..40.

CROSSREFS

Sequence in context: A378718 A077785 A222291 * A242571 A067144 A018784

Adjacent sequences: A015643 A015644 A015645 * A015647 A015648 A015649

KEYWORD

nonn

AUTHOR

Olivier Gérard

STATUS

approved