A206258 - cp's OEIS frontend

A206258 1/8 the number of 2 X 2 -n..n arrays with a 2 X 2 -n..n inverse, i.e., with determinant +-1.

n	a(n)
1	5
2	13
3	29
4	45
5	77
6	93
7	141
8	173
9	221
10	253
11	333
12	365
13	461
14	509
15	573
16	637
17	765
18	813
19	957
20	1021
21	1117
22	1197
23	1373
24	1437
25	1597
26	1693
27	1837
28	1933
29	2157
30	2221
31	2461
32	2589
33	2749
34	2877
35	3069
36	3165
37	3453
38	3597
39	3789
40	3917
41	4237
42	4333
43	4669
44	4829
45	5021
46	5197
47	5565

[5, 13, 29, 45, 77, 93, 141, 173, 221, 253, 333, 365, 461, 509, 573, 637, 765, 813, 957, 1021, 1117, 1197, 1373, 1437, 1597, 1693, 1837, 1933, 2157, 2221, 2461, 2589, 2749, 2877, 3069, 3165, 3453, 3597, 3789, 3917, 4237, 4333, 4669, 4829, 5021, 5197, 5565]

cp's OEIS Frontend

A206258 1/8 the number of 2 X 2 -n..n arrays with a 2 X 2 -n..n inverse, i.e., with determinant +-1.

Table of values

List of values