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A045924 Numbers n such that prime(n) == -1 (mod n). 15
1, 2, 3, 4, 10, 70, 72, 182, 440, 1053, 6458, 6461, 6471, 40087, 40089, 251737, 251742, 637320, 637334, 637336, 1617173, 4124466, 10553445, 10553455, 10553569, 10553570, 10553574, 10553576, 10553819, 10553829, 27067100, 27067262 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

LINKS

Labos, E. Graph of first 50000 terms

EXAMPLE

10 is a member because the 10th prime, 29, is congruent to -1 mod 10.

MATHEMATICA

NextPrim[n_] := Block[{k = n + 1}, While[ !PrimeQ[k], k++ ]; k]; p = 1; Do[ If[Mod[p = NextPrim[p], n] == n - 2, Print[n]], {n, 1, 10^9}] (from Robert G. Wilson v Feb 18 2004)

CROSSREFS

Cf. A004648 and esp. A023143.

Cf. A052013, A048891, A092044, A092045, A092046, A092047, A092048, A092049, A092050, A092051, A092052.

Sequence in context: A139009 A191224 A049204 * A068910 A146027 A035358

Adjacent sequences:  A045921 A045922 A045923 * A045925 A045926 A045927

KEYWORD

nonn

AUTHOR

Len Smiley (smiley(AT)math.uaa.alaska.edu)

EXTENSIONS

More terms from Patrick De Geest (pdg(AT)worldofnumbers.com), Nov 15 1999.

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Last modified February 17 07:41 EST 2012. Contains 205998 sequences.