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A355274
Numbers having more even than odd digits when written in base 3.
0
0, 2, 6, 8, 9, 11, 15, 17, 18, 19, 20, 21, 23, 24, 25, 26, 27, 29, 33, 35, 45, 47, 51, 53, 54, 55, 56, 57, 59, 60, 61, 62, 63, 65, 69, 71, 72, 73, 74, 75, 77, 78, 79, 80, 81, 82, 83, 84, 86, 87, 88, 89, 90, 92, 96, 98, 99, 100, 101, 102, 104, 105, 106, 107, 108, 110, 114, 116
OFFSET
1,2
PROG
(PARI) select( {is_A355274(n)=vecsum(n=digits(n, 3)%2)*2<#n+!n}, [0..123])
(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 == 0)
print([k for k in range(117) if ok(k)]) # Michael S. Branicky, Jul 03 2022
CROSSREFS
Cf. A072603 (same in base 2), A352546 (same in base 10).
Sequence in context: A366059 A043341 A023714 * A096507 A288428 A050675
KEYWORD
nonn,base
AUTHOR
M. F. Hasler, Jul 03 2022
STATUS
approved