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A179027 Primes with a 3 as the only prime digit. 2
3, 13, 31, 43, 83, 103, 113, 131, 139, 163, 193, 311, 349, 389, 431, 439, 443, 463, 613, 631, 643, 683, 839, 863, 883, 983, 1013, 1031, 1039, 1063, 1093, 1103, 1163, 1193, 1301, 1319, 1361, 1381, 1399, 1439, 1483, 1493, 1613, 1663, 1693, 1831, 1913, 1931 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
The digit 3 must appear only once. - Harvey P. Dale, Oct 12 2023
LINKS
MAPLE
filter:= proc(n) local L, t;
L:= convert(n, base, 10);
numboccur(3, L) = 1 and convert(L, set) intersect {2, 5, 7} = {}
end proc:
select(filter, [seq(ithprime(i), i=1..1000)]); # Robert Israel, Apr 21 2021
MATHEMATICA
Select[Prime[Range[300]], DigitCount[#, 10, 3]==1&&DigitCount[#, 10, 2]== DigitCount[#, 10, 5]== DigitCount[#, 10, 7]==0&] (* Harvey P. Dale, Oct 12 2023 *)
PROG
(Python)
from sympy import sieve
def ok(p): s=str(p); return set(s)&set("2357")=={'3'} and s.count('3')==1
def aupto(limit): return [p for p in sieve.primerange(1, limit+1) if ok(p)]
print(aupto(1931)) # Michael S. Branicky, Apr 21 2021
CROSSREFS
Cf. A179026.
Sequence in context: A248368 A171517 A179026 * A145907 A054554 A051939
KEYWORD
nonn,base
AUTHOR
Lekraj Beedassy, Jun 25 2010
EXTENSIONS
Corrected by Ray Chandler, Jul 13 2010
STATUS
approved

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Last modified July 12 23:13 EDT 2024. Contains 374257 sequences. (Running on oeis4.)