A261183 Primes that contain only the digits (4, 7, 9).

7, 47, 79, 97, 449, 479, 499, 797, 947, 977, 997, 4447, 4799, 4999, 7477, 7499, 7949, 9479, 9497, 9749, 9949, 44449, 44497, 44777, 44797, 47497, 47777, 47779, 47797, 47947, 47977, 49477, 49499, 49747, 49999, 74449, 74747, 74779, 74797, 77447, 77477, 77479

Offset

1,1

Comments

A020465, A020466 and A020471 are subsequences.

Links

Alois P. Heinz, Table of n, a(n) for n = 1..20000

James Maynard and Brady Haran, Primes without a 7, Numberphile video (2019)

Mathematica

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

Prog

(Magma) [p: p in PrimesUpTo(2*10^5) | Set(Intseq(p)) subset [4, 7, 9]];

Crossrefs

Cf. similar sequences listed in A261181.

Cf. A000040, A020465, A020466, A020471.

Sequence in context: A245229 A141882 A240569 * A067658 A044490 A139916

Adjacent sequences: A261180 A261181 A261182 * A261184 A261185 A261186

Keyword

nonn,easy,base

Author

Vincenzo Librandi, Aug 11 2015

Status

approved