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A178387
Primes p such that q*p+-Mod(p,q) are primes, for q=7.
1
41, 419, 839, 1259, 1889, 2239, 3541, 4801, 5039, 5711, 6229, 7349, 7699, 7741, 9239, 10429, 10891, 11171, 11801, 12809, 13159, 14629, 15889, 16631, 16981, 17891, 18661, 18899, 20089, 21559, 21601, 22651, 22679, 23981, 24989, 25969, 26879
OFFSET
1,1
COMMENTS
7*41=287+-6->primes,..
MATHEMATICA
q=7; lst={}; Do[p=Prime[n]; If[PrimeQ[q*p-Mod[p, q]]&&PrimeQ[q*p+Mod[p, q]], AppendTo[lst, p]], {n, 8!}]; lst
Select[Prime[Range[3000]], AllTrue[7#+{Mod[#, 7], -Mod[#, 7]}, PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Feb 13 2019 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved