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A178554 Primes with exactly five 5's. 5
555557, 1555553, 2555551, 3555551, 3555557, 4555559, 5055551, 5055559, 5355551, 5505551, 5535559, 5550553, 5550557, 5554553, 5555057, 5555059, 5555357, 5555507, 5555509, 5555527, 5555567, 5555591, 5555653, 5556557, 5556559, 5557553 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Daniel Starodubtsev, Table of n, a(n) for n = 1..10000

MATHEMATICA

Select[Prime[Range[PrimePi[55555], 1000000]], Count[IntegerDigits[#], 5]==5&]  (* Harvey P. Dale, Dec. 20, 2010 *)

PROG

(PARI) isok(p) = isprime(p) && (#select(x->(x==5), digits(p)) == 5); \\ Michel Marcus, Mar 15 2020

CROSSREFS

Cf. A038618, A178550, A178551, A178552, A178553, A178555, A178556, A178557, A178558.

Sequence in context: A346352 A196511 A196733 * A272133 A202720 A235969

Adjacent sequences:  A178551 A178552 A178553 * A178555 A178556 A178557

KEYWORD

nonn,base

AUTHOR

Lekraj Beedassy, May 29 2010

EXTENSIONS

Missing a(14) = 5554553 inserted by Daniel Starodubtsev, Mar 15 2020

STATUS

approved

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Last modified August 2 02:53 EDT 2021. Contains 346409 sequences. (Running on oeis4.)