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A068831
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Primes with all odd digits such that the next three primes also contain all odd digits.
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3
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3, 5, 7, 11, 191, 311, 313, 9133, 9371, 11113, 11171, 15731, 15937, 15959, 17939, 17957, 19319, 19553, 19739, 19973, 19979, 31151, 31333, 31511, 33353, 35573, 35753, 39113, 39119, 39937, 51131, 51133, 51971, 53717, 53719, 53731, 55313, 55331
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OFFSET
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1,1
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LINKS
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EXAMPLE
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313 belongs to this sequence as the next three primes 317, 331 and 337 contain only odd digits.
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MATHEMATICA
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odQ[n_] := And @@ OddQ[Flatten[IntegerDigits[Join[{n}, Table[NextPrime[n, k], {k, 3}]]]]]; Select[Prime[Range[5700]], odQ] (* Jayanta Basu, Aug 07 2013 *)
Prime[#]&/@SequencePosition[Table[If[AllTrue[IntegerDigits[p], OddQ], 1, 0], {p, Prime[Range[ 6000]]}], {1, 1, 1, 1}][[;; , 1]] (* Harvey P. Dale, Apr 02 2023 *)
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PROG
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(Magma) [NthPrime(n): n in [1..10^4] | forall{NthPrime(n+i): i in [0..3] | Intseq(NthPrime(n+i)) subset [1..9 by 2]}]; // Bruno Berselli, Aug 08 2013
(Python)
from itertools import product
from sympy import isprime, nextprime
A068831_list = [p for p in (int(''.join(d)) for l in range(1, 9) for d in product('13579', repeat=l)) if isprime(p) and set(str(nextprime(p, 1))) <= {'1', '3', '5', '7', '9'} and set(str(nextprime(p, 2))) <= {'1', '3', '5', '7', '9'} and set(str(nextprime(p, 3))) <= {'1', '3', '5', '7', '9'} ] # Chai Wah Wu, Aug 13 2015
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CROSSREFS
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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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Missing term a(19)=19739 supplied by Jayanta Basu, Aug 07 2013
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STATUS
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approved
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