A064260 Values of m such that N=(am+1)(bm+1)(cm+1) is a 3-Carmichael number (A087788), where a,b,c = 1,2,47.

210, 2466, 4158, 5850, 14028, 116958, 156156, 166026, 176178, 188868, 208608, 225528, 232860, 241320, 252036, 284748, 290106, 290670, 345378, 350736, 399240, 439566, 444078, 448308, 450000, 498786, 582540, 669678, 708030, 722976, 746100, 809268, 813216, 860028

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

carmQ[n_] := CompositeQ[n] && Divisible[n - 1, CarmichaelLambda[n]]; Select[Range[10^5], AllTrue[(v = {1, 2, 47}*# + 1), PrimeQ] && carmQ[Times @@ v] &] (* Amiram Eldar, Oct 17 2019 *)

Extensions

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