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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 (list; graph; refs; listen; history; text; internal format)
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

Jens Kruse Andersen, Table of n, a(n) for n = 1..10000

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

Cf. A245622, A245626.

Sequence in context: A133213 A138465 A006598 * A106892 A116893 A106066

Adjacent sequences:  A245620 A245621 A245622 * A245624 A245625 A245626

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

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Last modified May 22 09:50 EDT 2022. Contains 353949 sequences. (Running on oeis4.)