A015645 - OEIS

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A015645

Number of 5-tuples of different integers from [ 2,n ] with no common factors among quadruples.

0, 0, 0, 0, 1, 6, 18, 52, 105, 226, 374, 688, 1047, 1690, 2406, 3696, 4901, 7140, 9291, 12688, 16091, 21710, 26434, 34648, 42081, 53026, 63410, 79828, 92681, 114846, 133893, 160907, 185809, 223366, 252656, 301436, 342197, 398606, 448676

(list; graph; refs; listen; history; text; internal format)

OFFSET

2,6

LINKS

Table of n, a(n) for n=2..40.

CROSSREFS

Sequence in context: A318160 A220227 A075650 * A001216 A318484 A079843

Adjacent sequences: A015642 A015643 A015644 * A015646 A015647 A015648

KEYWORD

nonn

AUTHOR

Olivier Gérard

STATUS

approved