A209994 - cp's OEIS frontend

A209994 Number of 2 X 2 matrices with all elements in {1,2,...,n} and determinant in {-1,0,1}.

n	a(n)
0	0
1	1
2	10
3	31
4	60
5	105
6	154
7	223
8	300
9	393
10	490
11	607
12	748
13	889
14	1034
15	1215
16	1404
17	1593
18	1818
19	2031
20	2300
21	2569
22	2810
23	3071
24	3436
25	3753
26	4042
27	4399
28	4796
29	5129
30	5610
31	5967
32	6412
33	6857
34	7242
35	7759
36	8380
37	8809
38	9242
39	9775
40	10460

[0, 1, 10, 31, 60, 105, 154, 223, 300, 393, 490, 607, 748, 889, 1034, 1215, 1404, 1593, 1818, 2031, 2300, 2569, 2810, 3071, 3436, 3753, 4042, 4399, 4796, 5129, 5610, 5967, 6412, 6857, 7242, 7759, 8380, 8809, 9242, 9775, 10460]

cp's OEIS Frontend

A209994 Number of 2 X 2 matrices with all elements in {1,2,...,n} and determinant in {-1,0,1}.

Table of values

List of values