OFFSET
1,1
COMMENTS
Shanks noted that among the first 300 Carmichael numbers only 3 are in this sequence.
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000 (calculated using data from Claude Goutier)
Paul Erdős, On pseudoprimes and Carmichael numbers, Publ. Math. Debrecen 4 (1956), pp. 201-206.
Claude Goutier, Compressed text file carm10e22.gz containing all the Carmichael numbers up to 10^22.
Andrew Granville and Carl Pomerance, Two contradictory conjectures concerning Carmichael numbers, Mathematics of Computation, Vol. 71, No. 238 (2002), pp. 883-908.
Daniel Shanks, Solved and Unsolved Problems in Number Theory, 2nd ed., Chelsea Pub. Co., New York, 1978, p. 229.
MATHEMATICA
aQ[n_] := CompositeQ[n] && Divisible[n-1, CarmichaelLambda[n]] && AllTrue[FactorInteger[n][[;; , 1]] - 1, SquareFreeQ]; Select[Range[10^8], aQ]
CROSSREFS
KEYWORD
nonn
AUTHOR
Amiram Eldar, Oct 31 2019
STATUS
approved