A336400 - cp's OEIS frontend

A336400 The hafnian of a symmetric Toeplitz matrix of order 2*n, n>=2 with the first row (0,2,1,...,1,2); a(0)=1, a(1)=2.

n	a(n)
0	1
1	2
2	9
3	44
4	303
5	2697
6	29438
7	380529
8	5683359
9	96290588
10	1824544857
11	38229811083
12	877643031554
13	21906313145979
14	590665804363833
15	17109084307014332
16	529833078045763263
17	17468521692479218209
18	610901505126064857854
19	22586913755160674065113

[1, 2, 9, 44, 303, 2697, 29438, 380529, 5683359, 96290588, 1824544857, 38229811083, 877643031554, 21906313145979, 590665804363833, 17109084307014332, 529833078045763263, 17468521692479218209, 610901505126064857854, 22586913755160674065113]

cp's OEIS Frontend

A336400 The hafnian of a symmetric Toeplitz matrix of order 2*n, n>=2 with the first row (0,2,1,...,1,2); a(0)=1, a(1)=2.

Table of values

List of values