A225605 - cp's OEIS frontend

A225605 a(1) = least k such that 1/3 < H(k) - 1/3; a(2) = least k such that H(a(1)) - H(3) < 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	5
2	9
3	16
4	29
5	53
6	97
7	178
8	327
9	601
10	1105
11	2032
12	3737
13	6873
14	12641
15	23250
16	42763
17	78653
18	144665
19	266080
20	489397
21	900141
22	1655617
23	3045154
24	5600911
25	10301681
26	18947745
27	34850336
28	64099761
29	117897841
30	216847937
31	398845538
32	733591315
33	1349284789
34	2481721641

[5, 9, 16, 29, 53, 97, 178, 327, 601, 1105, 2032, 3737, 6873, 12641, 23250, 42763, 78653, 144665, 266080, 489397, 900141, 1655617, 3045154, 5600911, 10301681, 18947745, 34850336, 64099761, 117897841, 216847937, 398845538, 733591315, 1349284789, 2481721641]

cp's OEIS Frontend

A225605 a(1) = least k such that 1/3 < H(k) - 1/3; a(2) = least k such that H(a(1)) - H(3) < 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