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A214710 Least m>0 such that n!-m and n!!-m are relatively prime. 2
2, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Clark Kimberling, Table of n, a(n) for n = 1..1000

EXAMPLE

gcd(45!-1,45!!-1) = 47, gcd(45!-2, 45!!-2) = 1, so a(45) = 2.

MATHEMATICA

Table[m = 1; While[GCD[n! - m, n!! - m] != 1, m++]; m, {n, 1, 140}]

CROSSREFS

Cf. A214711, the positions of 2 in A214710.

Sequence in context: A114116 A054532 A260415 * A120888 A031230 A244226

Adjacent sequences:  A214707 A214708 A214709 * A214711 A214712 A214713

KEYWORD

nonn,easy

AUTHOR

Clark Kimberling, Jul 27 2012

STATUS

approved

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Last modified April 18 03:59 EDT 2021. Contains 343072 sequences. (Running on oeis4.)