A020479 - cp's OEIS frontend

A020479 Number of noninvertible 2 X 2 matrices over Z/nZ (determinant is a divisor of 0).

n	a(n)
2	10
3	33
4	160
5	145
6	1008
7	385
8	2560
9	2673
10	7120
11	1441
12	16128
13	2353
14	26320
15	27585
16	40960
17	5185
18	81648
19	7201
20	113920
21	97713
22	155056
23	12673
24	258048
25	90625
26	299728
27	216513
28	421120
29	25201
30	671760
31	30721
32	655360
33	552321
34	866320
35	532945
36	1306368
37	51985

[10, 33, 160, 145, 1008, 385, 2560, 2673, 7120, 1441, 16128, 2353, 26320, 27585, 40960, 5185, 81648, 7201, 113920, 97713, 155056, 12673, 258048, 90625, 299728, 216513, 421120, 25201, 671760, 30721, 655360, 552321, 866320, 532945, 1306368, 51985]

cp's OEIS Frontend

A020479 Number of noninvertible 2 X 2 matrices over Z/nZ (determinant is a divisor of 0).

Table of values

List of values