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A112251
Numbers m such that m mod floor(log_2(m)) = 1.
3
5, 7, 10, 13, 17, 21, 25, 29, 36, 41, 46, 51, 56, 61, 67, 73, 79, 85, 91, 97, 103, 109, 115, 121, 127, 134, 141, 148, 155, 162, 169, 176, 183, 190, 197, 204, 211, 218, 225, 232, 239, 246, 253, 257, 265, 273, 281, 289, 297, 305, 313, 321, 329, 337, 345, 353, 361
OFFSET
1,1
COMMENTS
A112248(a(n)) = 1; subsequence of A112250.
LINKS
MAPLE
q:= m-> is(m mod ilog2(m)=1):
select(q, [$2..361])[]; # Alois P. Heinz, Jul 03 2026
PROG
(Python)
from oeis_sequences.OEISsequences import bisection
def A112251(n):
def f(x):
c, l, a = n+2+x, x.bit_length(), 2
for i in range(1, l-1):
c += (a-2)//i
a <<= 1
c -= (a-2)//i
if l>1:
c -= (x-1)//(l-1)-(a-2)//(l-1)
return c
return bisection(f, n, n) # Chai Wah Wu, Jul 02 2026
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Aug 30 2005
EXTENSIONS
Name clarified by Sean A. Irvine, Jul 02 2026
STATUS
approved