A144091 - cp's OEIS frontend

A144091 T(n,k) is the number of partial bijections (or subpermutations) of an n-element set of height k (height(alpha) = |Im(alpha)|) and with exactly 2 fixed points.

n	a(n)
2	1
3	3
4	0
5	6
6	12
7	6
8	10
9	60
10	90
11	20
12	15
13	180
14	630
15	660
16	135
17	21
18	420
19	2730
20	6720
21	5565
22	924
23	28
24	840
25	8820
26	39760
27	76020
28	51912
29	7420
30	36
31	1512
32	23436
33	168840
34	585900
35	917784
36	533988
37	66744

[1, 3, 0, 6, 12, 6, 10, 60, 90, 20, 15, 180, 630, 660, 135, 21, 420, 2730, 6720, 5565, 924, 28, 840, 8820, 39760, 76020, 51912, 7420, 36, 1512, 23436, 168840, 585900, 917784, 533988, 66744]

cp's OEIS Frontend

A144091 T(n,k) is the number of partial bijections (or subpermutations) of an n-element set of height k (height(alpha) = |Im(alpha)|) and with exactly 2 fixed points.

Table of values

List of values