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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

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)

MATHEMATICA

Select[Prime[Range[6 10^4]], Complement[IntegerDigits[#], {0, 7, 9}] == {} &]

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).

Cf. A000040, A020471.

Sequence in context: A156714 A106110 A082992 * A106107 A020471 A065902

Adjacent sequences:  A261178 A261179 A261180 * A261182 A261183 A261184

KEYWORD

nonn,easy,base

AUTHOR

Vincenzo Librandi, Aug 11 2015

STATUS

approved

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Last modified June 15 15:16 EDT 2021. Contains 345049 sequences. (Running on oeis4.)