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A285982
a(n) = n! (mod n + 3).
1
1, 1, 2, 0, 3, 0, 0, 0, 5, 0, 6, 0, 0, 0, 8, 0, 9, 0, 0, 0, 11, 0, 0, 0, 0, 0, 14, 0, 15, 0, 0, 0, 0, 0, 18, 0, 0, 0, 20, 0, 21, 0, 0, 0, 23, 0, 0, 0, 0, 0, 26, 0, 0, 0, 0, 0, 29, 0, 30, 0, 0, 0, 0, 0, 33, 0, 0, 0, 35, 0, 36, 0, 0, 0, 0, 0, 39, 0, 0, 0, 41, 0, 0
OFFSET
0,3
COMMENTS
Nonzero terms are a(2 * A130290(n) - 2) = A130290(n) for n > 1. - David A. Corneth, Apr 30 2017
LINKS
FORMULA
a(n) = A000142(n) (mod n + 3).
If n > 1 and a(n) > 0, a(n) = n/2 + 1 and n + 3 is a prime.
MAPLE
seq(n! mod (n+3), n=0..100); # Robert Israel, Apr 30 2017
PROG
(PARI) a(n) = n! % (n+3); \\ Michel Marcus, Apr 30 2017
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Apr 29 2017
STATUS
approved