A064256 Numbers m such that N=(am+1)(bm+1)(cm+1) is a 3-Carmichael number (A087788), where a,b,c = 1,2,39.

3528, 4620, 8208, 13668, 21858, 24978, 26538, 29268, 30828, 33870, 34260, 34728, 44088, 51030, 58128, 58440, 61560, 72948, 79578, 80670, 95568, 107580, 109608, 112338, 118188, 118890, 124350, 126690, 142758, 144708, 148530, 176220, 191898, 196578, 198528, 208590

Offset

1,1

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

Mathematica

carmQ[n_] := CompositeQ[n] && Divisible[n - 1, CarmichaelLambda[n]]; Select[Range[10^5], AllTrue[(v = {1, 2, 39}*# + 1), PrimeQ] && carmQ[Times @@ v] &] (* Amiram Eldar, Oct 17 2019 *)

Crossrefs

Cf. A087788.

Sequence in context: A267125 A241240 A035897 * A232555 A330841 A035779

Adjacent sequences: A064253 A064254 A064255 * A064257 A064258 A064259

Keyword

nonn

Author

N. J. A. Sloane, Sep 23 2001

Extensions

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

Status

approved