A163280 - cp's OEIS frontend

A163280 Square array read by antidiagonals where column k lists the numbers j whose largest divisor <= sqrt(j) is k.

n	a(n)
1	1
2	2
3	4
4	3
5	6
6	9
7	5
8	8
9	12
10	16
11	7
12	10
13	15
14	20
15	25
16	11
17	14
18	18
19	24
20	30
21	36
22	13
23	22
24	21
25	28
26	35
27	42
28	49
29	17
30	26
31	27
32	32
33	40
34	48
35	56
36	64
37	19
38	34
39	33
40	44
41	45
42	54
43	63
44	72
45	81
46	23
47	38
48	39
49	52
50	50
51	60
52	70
53	80
54	90
55	100
56	29
57	46
58	51
59	68
60	55
61	66
62	77
63	88
64	99
65	110
66	121
67	31
68	58
69	57
70	76
71	65
72	78
73	84
74	96
75	108
76	120
77	132
78	144

[1, 2, 4, 3, 6, 9, 5, 8, 12, 16, 7, 10, 15, 20, 25, 11, 14, 18, 24, 30, 36, 13, 22, 21, 28, 35, 42, 49, 17, 26, 27, 32, 40, 48, 56, 64, 19, 34, 33, 44, 45, 54, 63, 72, 81, 23, 38, 39, 52, 50, 60, 70, 80, 90, 100, 29, 46, 51, 68, 55, 66, 77, 88, 99, 110, 121, 31, 58, 57, 76, 65, 78, 84, 96, 108, 120, 132, 144]

cp's OEIS Frontend

A163280 Square array read by antidiagonals where column k lists the numbers j whose largest divisor <= sqrt(j) is k.

Table of values

List of values

n	a(n)
1	1
2	2
3	4
4	3
5	6
6	9
7	5
8	8
9	12
10	16
11	7
12	10
13	15
14	20
15	25
16	11
17	14
18	18
19	24
20	30
21	36
22	13
23	22
24	21
25	28
26	35
27	42
28	49
29	17
30	26
31	27
32	32
33	40
34	48
35	56
36	64
37	19
38	34
39	33
40	44
41	45
42	54
43	63
44	72
45	81
46	23
47	38
48	39
49	52
50	50
51	60
52	70
53	80
54	90
55	100
56	29
57	46
58	51
59	68
60	55
61	66
62	77
63	88
64	99
65	110
66	121
67	31
68	58
69	57
70	76
71	65
72	78
73	84
74	96
75	108
76	120
77	132
78	144

n	a(n)
1	1
2	2
3	4
4	3
5	6
6	9
7	5
8	8
9	12
10	16
11	7
12	10
13	15
14	20
15	25
16	11
17	14
18	18
19	24
20	30
21	36
22	13
23	22
24	21
25	28
26	35
27	42
28	49
29	17
30	26
31	27
32	32
33	40
34	48
35	56
36	64
37	19
38	34
39	33
40	44
41	45
42	54
43	63
44	72
45	81
46	23
47	38
48	39
49	52
50	50
51	60
52	70
53	80
54	90
55	100
56	29
57	46
58	51
59	68
60	55
61	66
62	77
63	88
64	99
65	110
66	121
67	31
68	58
69	57
70	76
71	65
72	78
73	84
74	96
75	108
76	120
77	132
78	144

n	a(n)
1	1
2	2
3	4
4	3
5	6
6	9
7	5
8	8
9	12
10	16
11	7
12	10
13	15
14	20
15	25
16	11
17	14
18	18
19	24
20	30
21	36
22	13
23	22
24	21
25	28
26	35
27	42
28	49
29	17
30	26
31	27
32	32
33	40
34	48
35	56
36	64
37	19
38	34
39	33
40	44
41	45
42	54
43	63
44	72
45	81
46	23
47	38
48	39
49	52
50	50
51	60
52	70
53	80
54	90
55	100
56	29
57	46
58	51
59	68
60	55
61	66
62	77
63	88
64	99
65	110
66	121
67	31
68	58
69	57
70	76
71	65
72	78
73	84
74	96
75	108
76	120
77	132
78	144