A275707 - cp's OEIS frontend

A275707 Number of partial functions f:{1,2,...,n}->{1,2,...,n} such that every element in the domain of definition of f is mapped to a fixed point or to an element that is undefined by f.

n	a(n)
0	1
1	2
2	8
3	38
4	216
5	1402
6	10156
7	80838
8	698704
9	6498674
10	64579284
11	681642238
12	7605025720
13	89318058858
14	1100376445564
15	14176837311158
16	190498308591264
17	2663482511782114
18	38667106019619748
19	581765160424218606
20	9055862445043643656
21	145619330650420134362

[1, 2, 8, 38, 216, 1402, 10156, 80838, 698704, 6498674, 64579284, 681642238, 7605025720, 89318058858, 1100376445564, 14176837311158, 190498308591264, 2663482511782114, 38667106019619748, 581765160424218606, 9055862445043643656, 145619330650420134362]

cp's OEIS Frontend

A275707 Number of partial functions f:{1,2,...,n}->{1,2,...,n} such that every element in the domain of definition of f is mapped to a fixed point or to an element that is undefined by f.

Table of values

List of values