A263987 - cp's OEIS frontend

A263987 Number of ways of ordering integers 1 to n such that each number is either a factor of or larger than its predecessor.

n	a(n)
0	1
1	1
2	2
3	4
4	14
5	28
6	164
7	328
8	2240
9	9970
10	63410
11	126820
12	1810514
13	3621028
14	31417838
15	294911038
16	3344414606
17	6688829212
18	121919523980
19	243839047960
20	5307482547686
21	56885719183654
22	468469574780468
23	936939149560936
24	33136077712470338
25	249693200433310492

[1, 1, 2, 4, 14, 28, 164, 328, 2240, 9970, 63410, 126820, 1810514, 3621028, 31417838, 294911038, 3344414606, 6688829212, 121919523980, 243839047960, 5307482547686, 56885719183654, 468469574780468, 936939149560936, 33136077712470338, 249693200433310492]

cp's OEIS Frontend

A263987 Number of ways of ordering integers 1 to n such that each number is either a factor of or larger than its predecessor.

Table of values

List of values