A134978 - cp's OEIS frontend

A134978 Number of 2 X 2 singular integer matrices with entries from {2,...,n}.

n	a(n)
1	0
2	1
3	6
4	15
5	28
6	53
7	74
8	111
9	152
10	209
11	246
12	339
13	384
14	473
15	582
16	695
17	756
18	917
19	986
20	1175
21	1340
22	1493
23	1578
24	1855
25	2008
26	2193
27	2398
28	2683
29	2792
30	3185
31	3302
32	3603
33	3880
34	4129
35	4446
36	4943
37	5084
38	5365
39	5698
40	6231
41	6388
42	6973
43	7138
44	7615
45	8172
46	8517
47	8698
48	9431

[0, 1, 6, 15, 28, 53, 74, 111, 152, 209, 246, 339, 384, 473, 582, 695, 756, 917, 986, 1175, 1340, 1493, 1578, 1855, 2008, 2193, 2398, 2683, 2792, 3185, 3302, 3603, 3880, 4129, 4446, 4943, 5084, 5365, 5698, 6231, 6388, 6973, 7138, 7615, 8172, 8517, 8698, 9431]

cp's OEIS Frontend

A134978 Number of 2 X 2 singular integer matrices with entries from {2,...,n}.

Table of values

List of values