A184593 - cp's OEIS frontend

A184593 5n - A101306: sum_{i=1..n} the last digit of prime(i).

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

[3, 5, 5, 3, 7, 9, 7, 3, 5, 1, 5, 3, 7, 9, 7, 9, 5, 9, 7, 11, 13, 9, 11, 7, 5, 9, 11, 9, 5, 7, 5, 9, 7, 3, -1, 3, 1, 3, 1, 3, -1, 3, 7, 9, 7, 3, 7, 9, 7, 3, 5, 1, 5, 9, 7, 9, 5, 9, 7, 11, 13, 15, 13, 17, 19, 17, 21, 19, 17, 13, 15, 11, 9, 11, 7, 9, 5, 3, 7, 3]

cp's OEIS Frontend

A184593 5n - A101306: sum_{i=1..n} the last digit of prime(i).

Table of values

List of values

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

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

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