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A152220 Primes p such that p^2 divides m!-1 for some integer m<p. 1
11, 31, 107, 571, 971 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Numbers n such that n! - 1 is divisible by a square see A152219.
a(6)=4931 [From Artur Jasinski, Nov 30 2008]
LINKS
MATHEMATICA
aa = {}; Do[If[(Sqrt[n! - 1] /. Sqrt[_] -> 1) > 1, Print[n]; AppendTo[aa, (Sqrt[n! - 1] /. Sqrt[_] -> 1)], {n, 1, 1000}]; aa (*Artur Jasinski*)
CROSSREFS
A152231, A152232 [From Artur Jasinski, Nov 30 2008]
Sequence in context: A192246 A124296 A223388 * A272263 A082712 A049090
KEYWORD
nonn
AUTHOR
Artur Jasinski, Nov 29 2008
STATUS
approved

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Last modified March 29 00:26 EDT 2024. Contains 371264 sequences. (Running on oeis4.)