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A245623
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Primes having more digits 3's than 1's.
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3
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3, 23, 37, 43, 53, 73, 83, 223, 233, 239, 263, 283, 293, 307, 313, 331, 337, 347, 349, 353, 359, 367, 373, 379, 383, 389, 397, 433, 439, 443, 463, 503, 523, 563, 593, 643, 653, 673, 683, 733, 739, 743, 773, 823, 839, 853, 863, 883, 937, 953, 983, 1033, 1303
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OFFSET
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1,1
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COMMENTS
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13 has the same number of 1's and 3's, so it is not in the sequence.
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LINKS
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MAPLE
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filter:= proc(n)
local L;
if not isprime(n) then return false fi;
L:= convert(n, base, 10);
numboccur(3, L) > numboccur(1, L);
end proc:
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PROG
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(PARI) nbd(n, d) = my(v=digits(n), m=0); for(i=1, #v, if(v[i]==d, m++)); m
select(n->nbd(n, 3)>nbd(n, 1), primes(300)) \\ Colin Barker, Jul 27 2014
(Python)
import sympy
from sympy import prime
for n in range(1, 10**3):
..s = str(prime(n))
..if s.count('3') > s.count('1'):
....print(int(s), end=', ')
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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