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A261182 Primes that contain only the digits (2, 7, 9). 2
2, 7, 29, 79, 97, 227, 229, 277, 727, 797, 929, 977, 997, 2297, 2729, 2777, 2797, 2927, 2999, 7229, 7297, 7727, 7927, 9227, 9277, 9929, 22229, 22277, 22279, 22727, 22777, 27277, 27299, 27779, 27799, 27997, 29297, 29927, 72227, 72229, 72277, 72727, 72797 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A020459, A020460 and A020471 are subsequences.

LINKS

Chai Wah Wu, Table of n, a(n) for n = 1..1000

MATHEMATICA

Select[Prime[Range[2 10^4]], Complement[IntegerDigits[#], {2, 7, 9}] == {} &]

PROG

(MAGMA) [p: p in PrimesUpTo(2*10^5) | Set(Intseq(p)) subset [2, 7, 9]];

(Python)

from gmpy2 import is_prime

from itertools import product

A261182_list = [int(''.join(d)) for l in range(1, 10) for d in product('279', repeat=l) if is_prime(int(''.join(d)))] # Chai Wah Wu, Aug 11 2015

CROSSREFS

Cf. similar sequences listed in A261181.

Cf. A000040, A020459, A020460, A020471.

Sequence in context: A158024 A166940 A166939 * A155186 A203969 A199581

Adjacent sequences:  A261179 A261180 A261181 * A261183 A261184 A261185

KEYWORD

nonn,easy,base

AUTHOR

Vincenzo Librandi, Aug 11 2015

STATUS

approved

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Last modified October 17 11:26 EDT 2019. Contains 328108 sequences. (Running on oeis4.)