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A065703
Values of m such that N = (m+1)(2m+1)(71m+1) is a 3-Carmichael number (A087788).
10
1170, 5430, 53568, 59106, 63366, 86370, 95316, 99576, 103836, 105966, 116190, 183498, 184776, 239730, 260178, 300648, 319818, 333450, 339840, 362418, 367530, 481698, 485958, 503850, 511518, 605238, 644856, 725370, 732186, 762006, 788418, 799920, 837408, 870210
OFFSET
1,1
LINKS
FORMULA
am+1, bm+1, cm+1 are primes and am|(N-1), bm|(N-1), cm|(N-1).
MATHEMATICA
CarmichaelNbrQ[n_] := ! PrimeQ@ n && Mod[n, CarmichaelLambda@ n] == 1; Select[ Range@ 1000000, PrimeQ[# + 1] && PrimeQ[2# + 1] && PrimeQ[71# + 1] && CarmichaelNbrQ[(# + 1)(2# + 1)(71# + 1)] &] (* Robert G. Wilson v, Aug 23 2012 *)
PROG
(PARI) for(m=1, 1e6, is_A002997((m+1)*(2*m+1)*(71*m+1)) & print1(m", ")) \\ - M. F. Hasler, Aug 23 2012
KEYWORD
nonn
AUTHOR
Harvey Dubner (harvey(AT)dubner.com), Nov 14 2001
EXTENSIONS
Definition simplified, missing terms inserted, and extended by M. F. Hasler, Aug 23 2012
More terms from Amiram Eldar, Oct 17 2019
STATUS
approved