A065702 Values of m such that N = (am+1)(bm+1)(cm+1) is a 3-Carmichael number (A087788), where a,b,c = 1,2,69.

378, 1068, 24390, 29220, 32118, 56130, 70620, 74760, 77658, 82350, 96978, 100980, 110640, 114228, 132858, 152040, 177018, 183090, 186678, 214830, 253608, 282588, 290040, 319158, 342480, 345378, 374358, 388710, 406788, 418380, 428040, 442530, 463230, 463920, 477720

Offset: 1

Author

Harvey Dubner (harvey(AT)dubner.com), Nov 14 2001

Keywords

• nonn

Links

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

Crossrefs

Cf. A064238-A064262, A065695-A065703, A087788.

Programs

Mathematica

CarmichaelNbrQ[n_] := ! PrimeQ@ n && Mod[n, CarmichaelLambda@ n] == 1; Select[ Range@ 500000, PrimeQ[# + 1] && PrimeQ[2# + 1] && PrimeQ[69# + 1] && CarmichaelNbrQ[(# + 1)(2# + 1)(69# + 1)] &] (* Robert G. Wilson v, Aug 23 2012 *)

Formula

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