A134434 - cp's OEIS frontend

A134434 Triangle read by rows: T(n,k) is the number of permutations of {1,2,...,n} having k even entries that are followed by a smaller entry (n>=0, k>=0).

n	a(n)
0	1
1	1
2	1
3	1
4	4
5	2
6	4
7	16
8	4
9	36
10	72
11	12
12	36
13	324
14	324
15	36
16	576
17	2592
18	1728
19	144
20	576
21	9216
22	20736
23	9216
24	576
25	14400
26	115200
27	172800
28	57600
29	2880
30	14400
31	360000
32	1440000
33	1440000
34	360000
35	14400
36	518400
37	6480000
38	17280000
39	12960000
40	2592000
41	86400

[1, 1, 1, 1, 4, 2, 4, 16, 4, 36, 72, 12, 36, 324, 324, 36, 576, 2592, 1728, 144, 576, 9216, 20736, 9216, 576, 14400, 115200, 172800, 57600, 2880, 14400, 360000, 1440000, 1440000, 360000, 14400, 518400, 6480000, 17280000, 12960000, 2592000, 86400]

cp's OEIS Frontend

A134434 Triangle read by rows: T(n,k) is the number of permutations of {1,2,...,n} having k even entries that are followed by a smaller entry (n>=0, k>=0).

Table of values

List of values