A242820 - cp's OEIS frontend

A242820 Number T(n,k) of permutations of [n] with exactly k occurrences of the consecutive step pattern up, down, down, down; triangle T(n,k), n>=0, 0<=k<=max(0,floor((n-1)/4)), read by rows.

n	a(n)
0	1
1	1
2	2
3	6
4	24
5	116
6	4
7	672
8	48
9	4536
10	504
11	34944
12	5376
13	302896
14	59488
15	496
16	2916992
17	697856
18	13952
19	30899616
20	8720448
21	296736
22	357080064
23	116109312
24	5812224
25	4470310976
26	1645662912
27	110697408
28	349504
29	60269056512
30	24776769024
31	2114735616
32	17730048

[1, 1, 2, 6, 24, 116, 4, 672, 48, 4536, 504, 34944, 5376, 302896, 59488, 496, 2916992, 697856, 13952, 30899616, 8720448, 296736, 357080064, 116109312, 5812224, 4470310976, 1645662912, 110697408, 349504, 60269056512, 24776769024, 2114735616, 17730048]

cp's OEIS Frontend

A242820 Number T(n,k) of permutations of [n] with exactly k occurrences of the consecutive step pattern up, down, down, down; triangle T(n,k), n>=0, 0<=k<=max(0,floor((n-1)/4)), read by rows.

Table of values

List of values