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A309871
Numbers n for which 18n+1, 18n+5, 18n+7, 18n+11, 18n+13 and 18n+17 are primes.
2
892, 2432, 156817, 806697, 822937, 1377022, 1389412, 1418007, 1619642, 1753552, 2017732, 2058647, 2329302, 2554142, 2703347, 3058772, 3135107, 3326522, 3391797, 3723457, 4126867, 4132782, 4171422, 4411837, 4610252, 6378487, 6440087, 6878987, 6897782, 6991547
OFFSET
1,1
MATHEMATICA
tot[n_] := Select[Range[n], CoprimeQ[#, n] &]; m = 18; t = tot[m]; aQ[n_] := AllTrue[m * n + t, PrimeQ]; Select[Range[10^6], aQ] (* Amiram Eldar, Aug 22 2019 *)
PROG
(SageMath)
x = 1
for i in range(5000000):
if (18*i+1 in Primes()
and 18*i+5 in Primes()
and 18*i+7 in Primes()
and 18*i+11 in Primes()
and 18*i+13 in Primes()
and 18*i+17 in Primes()):
print(str(x)+" "+str(i))
x += 1
CROSSREFS
KEYWORD
nonn
AUTHOR
Ely Golden, Aug 21 2019
STATUS
approved