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A044873
Numbers having, in base 2, (sum of even run lengths)=(sum of odd run lengths).
3
9, 11, 13, 133, 135, 140, 143, 146, 148, 150, 152, 154, 156, 161, 164, 166, 172, 175, 178, 180, 182, 189, 196, 198, 200, 202, 206, 210, 212, 214, 216, 218, 220, 225, 228, 230, 236, 239, 241, 245, 247, 2065, 2069, 2071, 2077
OFFSET
1,1
PROG
(Python)
from itertools import groupby
def ok(n):
rl_sums = [0, 0]
for k, g in groupby(bin(n)[2:]):
rl = len(list(g))
rl_sums[rl%2] += rl
return rl_sums[0] == rl_sums[1]
print(list(filter(ok, range(2078)))) # Michael S. Branicky, Sep 11 2021
KEYWORD
nonn,base
STATUS
approved