A380906 Primes without {3, 5} as digits.

2, 7, 11, 17, 19, 29, 41, 47, 61, 67, 71, 79, 89, 97, 101, 107, 109, 127, 149, 167, 179, 181, 191, 197, 199, 211, 227, 229, 241, 269, 271, 277, 281, 401, 409, 419, 421, 449, 461, 467, 479, 487, 491, 499, 601, 607, 617, 619, 641, 647, 661, 677, 691, 701, 709, 719, 727, 761, 769, 787, 797

Offset

1,1

Links

Alois P. Heinz, Table of n, a(n) for n = 1..10000 (first 3275 terms from Vincenzo Librandi)

Index to entries for primes with digits in a given set

Mathematica

Select[Prime[Range[120]], DigitCount[#, 10, 3]==0&&DigitCount[#, 10, 5]==0&]

Prog

(Magma) [p: p in PrimesUpTo(700) | not 3 in Intseq(p) and not 5 in Intseq(p) ];
(PARI) isok(p) = if (isprime(p), my(d=digits(p)); (#select(x->(x==3), d)==0) && (#select(x->(x==5), d)==0)); \\ Michel Marcus, Feb 10 2025
(Python)
from itertools import count, islice
from sympy import isprime
def A380906_gen(): # generator of terms
    return filter(isprime, (int(oct(n)[2:].translate({51:52, 52:54, 53:55, 54:56, 55:57})) for n in count(1)))
A380906_list = list(islice(A380906_gen(), 20)) # Chai Wah Wu, Feb 12 2025

Crossrefs

Intersection of A038611 and A038613.

Cf. A000040, A020462, A329760.

Sequence in context: A390617 A384918 A045371 * A356003 A386103 A063205

Adjacent sequences: A380903 A380904 A380905 * A380907 A380908 A380909

Keyword

base,nonn

Author

Vincenzo Librandi, Feb 09 2025

Status

approved