A355275 Numbers having more odd than even digits when written in base 3.

1, 4, 10, 12, 13, 14, 16, 22, 31, 37, 39, 40, 41, 43, 49, 67, 85, 91, 93, 94, 95, 97, 103, 109, 111, 112, 113, 115, 117, 118, 119, 120, 121, 122, 123, 124, 125, 127, 129, 130, 131, 133, 139, 145, 147, 148, 149, 151, 157, 175, 193, 199, 201, 202, 203, 205, 211, 229, 256, 274, 280, 282, 283, 284, 286, 292

Offset: 1

Author

M. F. Hasler, Jul 03 2022

Keywords

• nonn
• base

Comments

If k is a term, then so is 3*k+1. - Robert Israel, Mar 04 2024

Links

• Robert Israel, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A072600 (same in base 2), A352547 (same in base 10).

Programs

Maple

filter:= proc(n) local L;
  L:= convert(n,base,3);
  numboccur(1,L) > nops(L)/2
end proc:
select(filter, [$1..1000]); # Robert Israel, Mar 04 2024

PARI

select( {is_A355275(n)=vecsum(n=digits(n,3)%2)*2>#n}, [0..299])

Python

from sympy.ntheory import digits
def ok(n):
    d = digits(n, 3)[1:]
    return len(d) < 2*sum(1 for di in d if di%2)
print([k for k in range(293) if ok(k)]) # Michael S. Branicky, Jul 03 2022