A261181 Primes that contain only the digits (0, 7, 9).

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

Author

Vincenzo Librandi, Aug 11 2015

Keywords

• nonn
• easy
• base

Comments

A020471 is a subsequence.

Links

• Alois P. Heinz, Table of n, a(n) for n = 1..10000
• James Maynard and Brady Haran, Primes without a 7, Numberphile video (2019)

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).

Cf. A000040, A020471.

Programs

Magma

[p: p in PrimesUpTo(2*10^5) | Set(Intseq(p)) subset [0, 7, 9]];

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 *)