A211059 - cp's OEIS frontend

A211059 Number of 2 X 2 matrices having all terms in {1,...,n} and positive determinant.

n	a(n)
1	0
2	5
3	33
4	112
5	288
6	605
7	1145
8	1968
9	3176
10	4861
11	7161
12	10152
13	14040
14	18917
15	24961
16	32352
17	41312
18	51949
19	64585
20	79320
21	96472
22	116277
23	139025
24	164840
25	194184
26	227261
27	264385
28	305840
29	352096
30	403245
31	459945
32	522312
33	590840
34	665917

[0, 5, 33, 112, 288, 605, 1145, 1968, 3176, 4861, 7161, 10152, 14040, 18917, 24961, 32352, 41312, 51949, 64585, 79320, 96472, 116277, 139025, 164840, 194184, 227261, 264385, 305840, 352096, 403245, 459945, 522312, 590840, 665917]

cp's OEIS Frontend

A211059 Number of 2 X 2 matrices having all terms in {1,...,n} and positive determinant.

Table of values

List of values