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A015644 Number of 5-tuples of different integers from [ 1,n ] with no common factors among quadruples. 0
0, 0, 0, 0, 1, 6, 21, 52, 121, 226, 431, 688, 1167, 1726, 2651, 3696, 5441, 7140, 10059, 12941, 17287, 21710, 28659, 34724, 44705, 53942, 67131, 79828, 99171, 114846, 140665, 163317, 194706, 224008, 266997, 301436, 356761, 403846 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,6

LINKS

Table of n, a(n) for n=1..38.

CROSSREFS

Sequence in context: A276072 A135454 A069778 * A067680 A115052 A025203

Adjacent sequences:  A015641 A015642 A015643 * A015645 A015646 A015647

KEYWORD

nonn

AUTHOR

Olivier Gérard

STATUS

approved

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Last modified January 24 01:05 EST 2020. Contains 331178 sequences. (Running on oeis4.)