A343739 - cp's OEIS frontend

A343739 a(n) is the last digit to appear in sqrt(n) (or -1 if n is a square).

n	a(n)
1	-1
2	8
3	4
4	-1
5	5
6	6
7	8
8	5
9	-1
10	4
11	8
12	2
13	8
14	0
15	5
16	-1
17	8
18	3
19	1
20	0
21	3
22	3
23	6
24	0
25	-1
26	6
27	8
28	4
29	9
30	8
31	9
32	7
33	1
34	6
35	2
36	-1
37	4
38	3
39	1
40	1
41	9
42	1
43	9
44	1
45	1
46	4
47	7
48	4
49	-1
50	9
51	0
52	4
53	6
54	0
55	3
56	0
57	1
58	4
59	3
60	0
61	3
62	2
63	6
64	-1
65	1
66	7
67	0
68	7
69	5
70	1
71	0
72	6
73	9
74	9
75	9
76	5
77	5
78	9
79	2
80	3
81	-1
82	2
83	6
84	2

[-1, 8, 4, -1, 5, 6, 8, 5, -1, 4, 8, 2, 8, 0, 5, -1, 8, 3, 1, 0, 3, 3, 6, 0, -1, 6, 8, 4, 9, 8, 9, 7, 1, 6, 2, -1, 4, 3, 1, 1, 9, 1, 9, 1, 1, 4, 7, 4, -1, 9, 0, 4, 6, 0, 3, 0, 1, 4, 3, 0, 3, 2, 6, -1, 1, 7, 0, 7, 5, 1, 0, 6, 9, 9, 9, 5, 5, 9, 2, 3, -1, 2, 6, 2]

cp's OEIS Frontend

A343739 a(n) is the last digit to appear in sqrt(n) (or -1 if n is a square).

Table of values

List of values

n	a(n)
1	-1
2	8
3	4
4	-1
5	5
6	6
7	8
8	5
9	-1
10	4
11	8
12	2
13	8
14	0
15	5
16	-1
17	8
18	3
19	1
20	0
21	3
22	3
23	6
24	0
25	-1
26	6
27	8
28	4
29	9
30	8
31	9
32	7
33	1
34	6
35	2
36	-1
37	4
38	3
39	1
40	1
41	9
42	1
43	9
44	1
45	1
46	4
47	7
48	4
49	-1
50	9
51	0
52	4
53	6
54	0
55	3
56	0
57	1
58	4
59	3
60	0
61	3
62	2
63	6
64	-1
65	1
66	7
67	0
68	7
69	5
70	1
71	0
72	6
73	9
74	9
75	9
76	5
77	5
78	9
79	2
80	3
81	-1
82	2
83	6
84	2

n	a(n)
1	-1
2	8
3	4
4	-1
5	5
6	6
7	8
8	5
9	-1
10	4
11	8
12	2
13	8
14	0
15	5
16	-1
17	8
18	3
19	1
20	0
21	3
22	3
23	6
24	0
25	-1
26	6
27	8
28	4
29	9
30	8
31	9
32	7
33	1
34	6
35	2
36	-1
37	4
38	3
39	1
40	1
41	9
42	1
43	9
44	1
45	1
46	4
47	7
48	4
49	-1
50	9
51	0
52	4
53	6
54	0
55	3
56	0
57	1
58	4
59	3
60	0
61	3
62	2
63	6
64	-1
65	1
66	7
67	0
68	7
69	5
70	1
71	0
72	6
73	9
74	9
75	9
76	5
77	5
78	9
79	2
80	3
81	-1
82	2
83	6
84	2

n	a(n)
1	-1
2	8
3	4
4	-1
5	5
6	6
7	8
8	5
9	-1
10	4
11	8
12	2
13	8
14	0
15	5
16	-1
17	8
18	3
19	1
20	0
21	3
22	3
23	6
24	0
25	-1
26	6
27	8
28	4
29	9
30	8
31	9
32	7
33	1
34	6
35	2
36	-1
37	4
38	3
39	1
40	1
41	9
42	1
43	9
44	1
45	1
46	4
47	7
48	4
49	-1
50	9
51	0
52	4
53	6
54	0
55	3
56	0
57	1
58	4
59	3
60	0
61	3
62	2
63	6
64	-1
65	1
66	7
67	0
68	7
69	5
70	1
71	0
72	6
73	9
74	9
75	9
76	5
77	5
78	9
79	2
80	3
81	-1
82	2
83	6
84	2