A131754 - cp's OEIS frontend

A131754 Size of the largest subset of {1,2,...,n} such that no two distinct elements differ by a perfect square > 1.

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

[1, 2, 3, 4, 4, 4, 4, 4, 5, 5, 6, 6, 6, 7, 8, 8, 8, 8, 8, 8, 9, 10, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11, 11, 11, 12, 13, 13, 13, 13, 13, 14, 15, 15, 15, 15, 15, 15, 16, 17, 17, 17, 17, 17, 17, 18, 19, 19, 19, 19, 19, 19, 20, 20, 20, 20, 20, 20, 21, 21, 21, 21, 21, 21, 21, 22, 23, 24, 24, 24, 24, 24]

cp's OEIS Frontend

A131754 Size of the largest subset of {1,2,...,n} such that no two distinct elements differ by a perfect square > 1.

Table of values

List of values

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

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

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