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A309871 Numbers n for which 18n+1, 18n+5, 18n+7, 18n+11, 18n+13 and 18n+17 are primes. 1
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Ely Golden, Table of n, a(n) for n = 1..1001

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

Cf. A123986, A056956, A007811, A123985.

Sequence in context: A068752 A173349 A272932 * A063878 A063167 A210007

Adjacent sequences:  A309868 A309869 A309870 * A309872 A309873 A309874

KEYWORD

nonn

AUTHOR

Ely Golden, Aug 21 2019

STATUS

approved

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Last modified May 18 05:45 EDT 2022. Contains 353783 sequences. (Running on oeis4.)