A112857 - cp's OEIS frontend

A112857 Triangle T(n,k) read by rows: number of Green's R-classes in the semigroup of order-preserving partial transformations (of an n-element chain) consisting of elements of height k (height(alpha) = |Im(alpha)|).

n	a(n)
0	1
1	1
2	1
3	1
4	3
5	1
6	1
7	7
8	5
9	1
10	1
11	15
12	17
13	7
14	1
15	1
16	31
17	49
18	31
19	9
20	1
21	1
22	63
23	129
24	111
25	49
26	11
27	1
28	1
29	127
30	321
31	351
32	209
33	71
34	13
35	1
36	1
37	255
38	769
39	1023
40	769
41	351
42	97
43	15
44	1
45	1
46	511
47	1793
48	2815
49	2561
50	1471
51	545
52	127
53	17
54	1
55	1
56	1023
57	4097
58	7423
59	7937
60	5503
61	2561
62	799
63	161
64	19
65	1

[1, 1, 1, 1, 3, 1, 1, 7, 5, 1, 1, 15, 17, 7, 1, 1, 31, 49, 31, 9, 1, 1, 63, 129, 111, 49, 11, 1, 1, 127, 321, 351, 209, 71, 13, 1, 1, 255, 769, 1023, 769, 351, 97, 15, 1, 1, 511, 1793, 2815, 2561, 1471, 545, 127, 17, 1, 1, 1023, 4097, 7423, 7937, 5503, 2561, 799, 161, 19, 1]

cp's OEIS Frontend

A112857 Triangle T(n,k) read by rows: number of Green's R-classes in the semigroup of order-preserving partial transformations (of an n-element chain) consisting of elements of height k (height(alpha) = |Im(alpha)|).

Table of values

List of values