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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
OFFSET
1,1
LINKS
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: A054532 A260415 A370942 * A120888 A031230 A355032
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Jul 27 2012
STATUS
approved