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A245623
Primes having more digits 3's than 1's.
3
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
OFFSET
1,1
COMMENTS
13 has the same number of 1's and 3's, so it is not in the sequence.
See comment in A245626.
LINKS
MAPLE
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:
select(filter, [$1..1000]); # Robert Israel, Aug 03 2014
PROG
(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=', ')
# Derek Orr, Jul 28 2014
CROSSREFS
Sequence in context: A368691 A138465 A006598 * A106892 A370601 A116893
KEYWORD
nonn,base
AUTHOR
Vladimir Shevelev, Jul 27 2014
EXTENSIONS
More terms from Peter J. C. Moses, Jul 27 2014
More terms from Colin Barker, Jul 27 2014
STATUS
approved