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A020468 Primes that contain digits 5 and 9 only. 5
5, 59, 599, 59999, 95959, 99559, 599959, 599999, 995959, 999599, 999959, 5595559, 5595599, 5599999, 5955959, 5995999, 5999599, 9555599, 9559999, 9595559, 9955559, 9995599, 55555559, 55559599, 55595599, 55599959, 55959559, 59999999, 95559559 (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[{5, 9}, n], PrimeQ], {n, 8}]] (* Vincenzo Librandi, Jul 27 2012 *)

PROG

(MAGMA) [p: p in PrimesUpTo(95559559 ) | Set(Intseq(p)) subset [5, 9]]; // Vincenzo Librandi, Jul 27 2012

CROSSREFS

Sequence in context: A099151 A243219 A113055 * A093946 A249519 A001059

Adjacent sequences:  A020465 A020466 A020467 * A020469 A020470 A020471

KEYWORD

nonn,base

AUTHOR

David W. Wilson

STATUS

approved

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Last modified January 28 09:17 EST 2020. Contains 331318 sequences. (Running on oeis4.)