A064262 Values of m such that N=(am+1)(bm+1)(cm+1) is a 3-Carmichael number (A087788), where a,b,c = 1,2,51.

330, 1656, 1758, 6960, 11958, 14406, 27258, 30318, 30930, 31236, 37356, 40110, 43986, 44088, 50820, 53268, 55818, 63366, 65100, 67650, 71526, 74586, 81930, 90906, 93150, 94476, 98250, 99678, 109470, 119568, 121710, 129768, 135276, 141906, 146190, 147516, 155166

Offset: 1

Author

N. J. A. Sloane, Sep 23 2001

Keywords

• nonn

Comments

am+1, bm+1, cm+1 are primes and am | (N-1), bm | (N-1), cm |(N-1).

References

• Harvey Dubner (harvey(AT)dubner.com), personal communication, Jun 27 2001.

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A087788.

Programs

Mathematica

CarmichaelNbrQ[n_] := ! PrimeQ@ n && Mod[n, CarmichaelLambda[n]] == 1; Select[ Range@ 9000, PrimeQ[# + 1] && PrimeQ[2# + 1] && PrimeQ[51# + 1] && CarmichaelNbrQ[(# + 1)(2# + 1)(51# + 1)] &] (* Robert G. Wilson v, Aug 23 2012 *)

Extensions

Offset corrected and more terms added by Amiram Eldar, Oct 17 2019