

A154555


Primes p such that m=(p1)/2 is the least number such that p divides m!+1.


2



7, 11, 19, 43, 47, 127, 131, 163, 179, 191, 199, 263, 347, 367, 419, 431, 443, 491, 503, 523, 571, 619, 691, 727, 743, 787, 839, 863, 1051, 1087, 1091, 1123, 1291, 1319, 1367, 1451, 1487, 1499, 1571, 1579, 1583, 1667, 1723, 1783, 1823, 1931, 1951, 2003, 2039
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OFFSET

1,1


COMMENTS

The graph of A073944 shows two prominent curves. This sequence gives the primes on the lower curve. Primes on the upper curve are in sequence A154554.


LINKS

T. D. Noe, Table of n, a(n) for n=1..1000


MATHEMATICA

Rest[Reap[Do[p=Prime[i]; f=1; m=1; While[f=Mod[f*m, p]; f+1<p, m++ ]; If[m==(p1)/2, Sow[p]], {i, 400}]]][[1, 1]]


CROSSREFS

Sequence in context: A038984 A165549 A055939 * A285016 A162857 A307965
Adjacent sequences: A154552 A154553 A154554 * A154556 A154557 A154558


KEYWORD

nonn


AUTHOR

T. D. Noe, Jan 12 2009


STATUS

approved



