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A294028
Composite numbers k such that k | 1 - A078712(k).
1
49, 77, 121, 203, 319, 413, 679, 721, 749, 841, 869, 1057, 1211, 1351, 1393, 1397, 1441, 1639, 1687, 1757, 1769, 1883, 2167, 2189, 2219, 2359, 2429, 2581, 2651, 2761, 2959, 3031, 3073, 3101, 3227, 3409, 3437, 3485, 3487, 3563, 3899, 4037, 4039, 4109, 4279
OFFSET
1,1
COMMENTS
A018187 (restricted Perrin pseudoprimes) is the intersection of A013998 (unrestricted Perrin pseudoprimes) with this sequence.
LINKS
William Adams and Daniel Shanks, Strong primality tests that are not sufficient, Math. Comp. 39 (1982), 255-300.
MATHEMATICA
a={}; b=-Drop[CoefficientList[Series[(2x+3)/(x^3-x-1), {x, 0, 10^4}], x] , 1];
Do[If[!PrimeQ[k]&&Divisible[b[[k]]+1, k], AppendTo[a, k]], {k, 2, Length[b]}]; a
CROSSREFS
KEYWORD
nonn
AUTHOR
Amiram Eldar, Oct 22 2017
STATUS
approved