A079404 - cp's OEIS frontend

A079404 Let G(n) be the set of numbers between 2^(n-1) and 2^n-1, inclusive. There is a unique number m(n) in G(n) so that the denominator of the m(n)-th partial sum of the double harmonic series is divisible by smaller 2-power than that of others in G(n). This power is defined to be a(n).

n	a(n)
2	0
3	1
4	1
5	3
6	4
7	3
8	3
9	5
10	7
11	9
12	10
13	9
14	10
15	12
16	14
17	13
18	13
19	15
20	17
21	19
22	19

[0, 1, 1, 3, 4, 3, 3, 5, 7, 9, 10, 9, 10, 12, 14, 13, 13, 15, 17, 19, 19]