A228025 - cp's OEIS frontend

A228025 a(1) = least k such that 1/2+1/3+1/4+1/5 < H(k) - H(5); a(2) = least k such that H(a(1)) - H(5) < H(k) -H(a(1)), and for n > 2, a(n) = least k such that H(a(n-1)) - H(a(n-2)) > H(k) - H(a(n-1)), where H = harmonic number.

n	a(n)
1	20
2	76
3	285
4	1065
5	3976
6	14840
7	55385
8	206701
9	771420
10	2878980
11	10744501
12	40099025
13	149651600
14	558507376
15	2084377905
16	7779004245
17	29031639076
18	108347552060
19	404358569165
20	1509086724601
21	5631988329240
22	21018866592360
23	78443478040201
24	292755045568445

[20, 76, 285, 1065, 3976, 14840, 55385, 206701, 771420, 2878980, 10744501, 40099025, 149651600, 558507376, 2084377905, 7779004245, 29031639076, 108347552060, 404358569165, 1509086724601, 5631988329240, 21018866592360, 78443478040201, 292755045568445]

cp's OEIS Frontend

A228025 a(1) = least k such that 1/2+1/3+1/4+1/5 < H(k) - H(5); a(2) = least k such that H(a(1)) - H(5) < H(k) -H(a(1)), and for n > 2, a(n) = least k such that H(a(n-1)) - H(a(n-2)) > H(k) - H(a(n-1)), where H = harmonic number.

Table of values

List of values