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A153168
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Primes p with property that 6p+1 is prime and uses only digits 2 and 3.
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1
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37, 5387, 537037, 37220537, 38870537, 3703870537, 5555555387, 55538720387, 370553872037, 370555370387, 372203887037, 387037038887, 387203705387, 388887053887, 537203703887, 538705553887, 538722205537, 538870538887, 553703722037, 553720538887
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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(#-1)/6&/@Select[Flatten[Table[FromDigits/@Tuples[{2, 3}, n], {n, 13}]], AllTrue[ {#, (#-1)/6}, PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Dec 15 2015 *)
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PROG
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(PARI) okdig(n) = {digs = Set(digits(n)); (#digs == 2) && (digs[1] == 2) && (digs[2] == 3); }
lista(nn) = {p = 2; until (p > nn, if (isprime(q=6*p+1) && okdig(q), print1(p, ", ")); p = nextprime(p+1); ); } \\ Michel Marcus, Oct 15 2013
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CROSSREFS
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Cf. A153166 Numbers n with property that 6n+1 is prime and uses only digits 2 and 3.
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KEYWORD
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nonn,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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