A355761 - cp's OEIS frontend

A355761 a(n) is the number of grid points in a square lattice strictly outside of the area enclosed by n loops of an Archimedean spiral and inside (or on the boundary) of a circle with radius n.

n	a(n)
0	0
1	3
2	5
3	8
4	9
5	17
6	16
7	17
8	19
9	25
10	35
11	27
12	26
13	37
14	39
15	49
16	41
17	46
18	47
19	53
20	62
21	51
22	66
23	63
24	57
25	76
26	77
27	85
28	75
29	77
30	87
31	79
32	93
33	92
34	100
35	112
36	93
37	106
38	97
39	122
40	125
41	107
42	115
43	115
44	131
45	138
46	123
47	130
48	126
49	134
50	147
51	164
52	163
53	149
54	151
55	148
56	171
57	159
58	172
59	160
60	172
61	180
62	176

[0, 3, 5, 8, 9, 17, 16, 17, 19, 25, 35, 27, 26, 37, 39, 49, 41, 46, 47, 53, 62, 51, 66, 63, 57, 76, 77, 85, 75, 77, 87, 79, 93, 92, 100, 112, 93, 106, 97, 122, 125, 107, 115, 115, 131, 138, 123, 130, 126, 134, 147, 164, 163, 149, 151, 148, 171, 159, 172, 160, 172, 180, 176]

cp's OEIS Frontend

A355761 a(n) is the number of grid points in a square lattice strictly outside of the area enclosed by n loops of an Archimedean spiral and inside (or on the boundary) of a circle with radius n.

Table of values

List of values

n	a(n)
0	0
1	3
2	5
3	8
4	9
5	17
6	16
7	17
8	19
9	25
10	35
11	27
12	26
13	37
14	39
15	49
16	41
17	46
18	47
19	53
20	62
21	51
22	66
23	63
24	57
25	76
26	77
27	85
28	75
29	77
30	87
31	79
32	93
33	92
34	100
35	112
36	93
37	106
38	97
39	122
40	125
41	107
42	115
43	115
44	131
45	138
46	123
47	130
48	126
49	134
50	147
51	164
52	163
53	149
54	151
55	148
56	171
57	159
58	172
59	160
60	172
61	180
62	176

n	a(n)
0	0
1	3
2	5
3	8
4	9
5	17
6	16
7	17
8	19
9	25
10	35
11	27
12	26
13	37
14	39
15	49
16	41
17	46
18	47
19	53
20	62
21	51
22	66
23	63
24	57
25	76
26	77
27	85
28	75
29	77
30	87
31	79
32	93
33	92
34	100
35	112
36	93
37	106
38	97
39	122
40	125
41	107
42	115
43	115
44	131
45	138
46	123
47	130
48	126
49	134
50	147
51	164
52	163
53	149
54	151
55	148
56	171
57	159
58	172
59	160
60	172
61	180
62	176

n	a(n)
0	0
1	3
2	5
3	8
4	9
5	17
6	16
7	17
8	19
9	25
10	35
11	27
12	26
13	37
14	39
15	49
16	41
17	46
18	47
19	53
20	62
21	51
22	66
23	63
24	57
25	76
26	77
27	85
28	75
29	77
30	87
31	79
32	93
33	92
34	100
35	112
36	93
37	106
38	97
39	122
40	125
41	107
42	115
43	115
44	131
45	138
46	123
47	130
48	126
49	134
50	147
51	164
52	163
53	149
54	151
55	148
56	171
57	159
58	172
59	160
60	172
61	180
62	176