A087529 Primes consisting only of digits 3 and 4 occurring with equal frequency.

43, 34434343, 44334343, 44343433, 3334344443, 3343443443, 3344334443, 3344344343, 3344434433, 3433434443, 3433444433, 3434444333, 3443343443, 3444334343, 4334433443, 4334443433, 4343444333, 4344333443, 4344433343, 4344443333, 4433343443, 4433344343, 4434334343

Offset

1,1

Comments

There are 18 digit pairs which can produce such primes. (1,0),(1,3),(1,4),(1,6),(1,7),(1,9),(2,3),(2,9),(3,4),(3,5),(3,7),(3,8),(4,7),(4,9),(5,9),(6,7),(7,9),(8,9).

Links

Harvey P. Dale, Table of n, a(n) for n = 1..5000

Mathematica

Select[FromDigits/@Flatten[Permutations/@Table[PadRight[{}, 2n, {4, 3}], {n, 5}], 1], PrimeQ]//Sort (* Harvey P. Dale, Aug 08 2017 *)

Prog

(PARI) \\ Needs B() from A087510.
concat(vector(6, k, B(k, 3, 4, isprime))) \\ Andrew Howroyd, Sep 21 2024

Crossrefs

Cf. A087510, A087511, A087528.

Sequence in context: A125828 A177417 A116139 * A050525 A138086 A023933

Adjacent sequences: A087526 A087527 A087528 * A087530 A087531 A087532

Keyword

base,nonn

Author

Paul D. Hanna and Amarnath Murthy, Sep 12 2003

Status

approved