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A044054
Numbers k such that string 0,2 occurs in the base-3 representation of k but not of k-1.
1
11, 20, 29, 33, 38, 47, 56, 60, 65, 74, 83, 87, 92, 99, 110, 114, 119, 128, 137, 141, 146, 155, 164, 168, 173, 180, 191, 195, 200, 209, 218, 222, 227, 236, 245, 249, 254, 261, 272, 276, 281, 290, 297, 326, 330, 335, 342, 353, 357, 362, 371, 380, 384, 389, 398
OFFSET
1,1
PROG
(Python)
from sympy.ntheory import digits
def cond(n): return "02" in "".join(map(str, digits(n, 3)))
def ok(n): return cond(n) and not cond(n-1)
print([k for k in range(400) if ok(k)]) # Michael S. Branicky, Nov 20 2021
CROSSREFS
Sequence in context: A250203 A339307 A038581 * A044435 A302563 A011753
KEYWORD
nonn,base
STATUS
approved