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A064250 Values of m such that N=(am+1)(bm+1)(cm+1) is a 3-Carmichael number (A087788), where a,b,c = 1,2,27. 1
606, 2280, 3036, 3738, 7950, 15348, 16266, 20640, 21558, 23826, 26040, 27066, 28686, 30576, 31386, 31656, 32358, 33870, 36570, 47856, 49476, 53148, 57036, 64920, 65028, 70536, 72480, 80526, 85818, 86466, 92568, 94350, 96996, 102828 (list; graph; refs; listen; history; text; internal format)
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

CarmichaelNbrQ[n_] := ! PrimeQ@ n && Mod[n, CarmichaelLambda@ n] == 1; Select[ Range@ 105000, PrimeQ[# + 1] && PrimeQ[2# + 1] && PrimeQ[27# + 1] && CarmichaelNbrQ[(# + 1)(2# + 1)(27# + 1)] &] (* Robert G. Wilson v, Aug 23 2012 *)

CROSSREFS

Cf. A087788.

Sequence in context: A228036 A274765 A249524 * A186818 A283639 A332160

Adjacent sequences:  A064247 A064248 A064249 * A064251 A064252 A064253

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Sep 23 2001

EXTENSIONS

Offset corrected by Amiram Eldar, Oct 17 2019

STATUS

approved

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Last modified December 7 20:40 EST 2021. Contains 349589 sequences. (Running on oeis4.)