A104557 - cp's OEIS frontend

A104557 Triangle T, read by rows, such that the unsigned columns of the matrix inverse when read downwards equals the rows of T read backwards, with T(n,n)=1 and T(n,n-1) = floor((n+1)/2)*floor((n+2)/2).

n	a(n)
0	1
1	1
2	1
3	2
4	2
5	1
6	6
7	6
8	4
9	1
10	24
11	24
12	18
13	6
14	1
15	120
16	120
17	96
18	36
19	9
20	1
21	720
22	720
23	600
24	240
25	72
26	12
27	1
28	5040
29	5040
30	4320
31	1800
32	600
33	120
34	16
35	1
36	40320
37	40320
38	35280
39	15120
40	5400
41	1200
42	200
43	20
44	1
45	362880
46	362880
47	322560
48	141120
49	52920
50	12600
51	2400
52	300
53	25
54	1

[1, 1, 1, 2, 2, 1, 6, 6, 4, 1, 24, 24, 18, 6, 1, 120, 120, 96, 36, 9, 1, 720, 720, 600, 240, 72, 12, 1, 5040, 5040, 4320, 1800, 600, 120, 16, 1, 40320, 40320, 35280, 15120, 5400, 1200, 200, 20, 1, 362880, 362880, 322560, 141120, 52920, 12600, 2400, 300, 25, 1]

cp's OEIS Frontend

A104557 Triangle T, read by rows, such that the unsigned columns of the matrix inverse when read downwards equals the rows of T read backwards, with T(n,n)=1 and T(n,n-1) = floor((n+1)/2)*floor((n+2)/2).

Table of values

List of values