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A020461 Primes that contain digits 3 and 4 only. 12
3, 43, 433, 443, 3343, 3433, 33343, 333433, 334333, 343333, 343433, 444343, 444443, 3333433, 3343343, 3343433, 3344333, 3344443, 3433333, 3434443, 3443443, 3444443, 4344443, 4433333, 4434343, 4443433, 34333333, 34434343, 34444343, 43444433 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

MATHEMATICA

Flatten[Table[Select[FromDigits/@Tuples[{3, 4}, n], PrimeQ], {n, 8}]] (* Vincenzo Librandi, Jul 27 2012 *)

PROG

(MAGMA) [p: p in PrimesUpTo(43444433) | Set(Intseq(p)) subset [3, 4]];

// Bruno Berselli, Jul 27 2012

CROSSREFS

Cf. A054356.

Sequence in context: A197609 A199346 A199340 * A138974 A036940 A099664

Adjacent sequences:  A020458 A020459 A020460 * A020462 A020463 A020464

KEYWORD

nonn,base

AUTHOR

David W. Wilson

STATUS

approved

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Last modified October 19 15:50 EDT 2019. Contains 328223 sequences. (Running on oeis4.)