A209992 - cp's OEIS frontend

A209992 Number of 2 X 2 matrices with all elements in {1,2,...,n} and determinant in {0,1}.

n	a(n)
0	0
1	1
2	8
3	23
4	46
5	77
6	120
7	167
8	230
9	301
10	384
11	463
12	590
13	685
14	808
15	959
16	1118
17	1245
18	1448
19	1591
20	1830
21	2053
22	2256
23	2431
24	2766
25	3005
26	3248
27	3535
28	3886
29	4109
30	4560
31	4799
32	5182
33	5549
34	5872
35	6295
36	6870
37	7157
38	7520
39	7959
40	8582

[0, 1, 8, 23, 46, 77, 120, 167, 230, 301, 384, 463, 590, 685, 808, 959, 1118, 1245, 1448, 1591, 1830, 2053, 2256, 2431, 2766, 3005, 3248, 3535, 3886, 4109, 4560, 4799, 5182, 5549, 5872, 6295, 6870, 7157, 7520, 7959, 8582]

cp's OEIS Frontend

A209992 Number of 2 X 2 matrices with all elements in {1,2,...,n} and determinant in {0,1}.

Table of values

List of values