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A261181
Primes that contain only the digits (0, 7, 9).
4
7, 79, 97, 709, 797, 907, 977, 997, 7079, 7907, 9007, 9907, 70009, 70079, 70099, 70709, 70979, 70997, 70999, 77797, 77977, 77999, 79777, 79907, 79979, 79997, 79999, 90007, 90709, 90907, 90977, 90997, 97007, 97777, 99079, 99707, 99709, 99907, 700079
OFFSET
1,1
COMMENTS
A020471 is a subsequence.
LINKS
James Maynard and Brady Haran, Primes without a 7, Numberphile video (2019)
MATHEMATICA
Select[Prime[Range[6 10^4]], Complement[IntegerDigits[#], {0, 7, 9}] == {} &]
Select[FromDigits/@Tuples[{0, 7, 9}, 6], PrimeQ] (* Harvey P. Dale, Aug 09 2024 *)
PROG
(Magma) [p: p in PrimesUpTo(2*10^5) | Set(Intseq(p)) subset [0, 7, 9]];
CROSSREFS
Cf. Primes that contain only the digits (k,7,9): this sequence (k=0), A260893 (k=1), A261182 (k=2), A260382 (k=3), A261183 (k=4), A260831 (k=5), A261184 (k=6), A106110 (k=8).
Sequence in context: A350964 A106110 A082992 * A106107 A020471 A065902
KEYWORD
nonn,easy,base
AUTHOR
Vincenzo Librandi, Aug 11 2015
STATUS
approved