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A078331
First prime such that p^2==1 (mod n).
0
2, 3, 2, 3, 11, 5, 13, 3, 17, 11, 23, 5, 53, 13, 11, 7, 67, 17, 37, 11, 13, 23, 47, 5, 101, 53, 53, 13, 59, 11, 61, 17, 23, 67, 29, 17, 73, 37, 53, 11, 83, 13, 173, 23, 19, 47, 281, 7, 97, 101, 67, 53, 107, 53, 89, 13, 37, 59, 353, 11, 367, 61, 71, 31, 79, 23, 269, 67, 47, 29
OFFSET
1,1
EXAMPLE
a(2)=3 because 3^2=9==1 (mod 2), while 2^2==0 (mod 2).
PROG
(PARI) for (n=1, 100, forprime(p=2, 1000, if ((p^2-1)%n==0, print1(p", "); break)))
CROSSREFS
Sequence in context: A117936 A264766 A251090 * A093868 A194603 A183465
KEYWORD
nonn
AUTHOR
Jon Perry, Nov 21 2002
STATUS
approved