A121369 - cp's OEIS frontend

A121369 a(1) = a(2) = 1, a(n) = A007947(a(n-1)) + A007947(a(n-2)) for n >= 3, i.e., a(n) is the largest squarefree divisor of a(n-1) plus the largest squarefree divisor of a(n-2).

n	a(n)
1	1
2	1
3	2
4	3
5	5
6	8
7	7
8	9
9	10
10	13
11	23
12	36
13	29
14	35
15	64
16	37
17	39
18	76
19	77
20	115
21	192
22	121
23	17
24	28
25	31
26	45
27	46
28	61
29	107
30	168
31	149
32	191
33	340
34	361
35	189
36	40
37	31
38	41
39	72
40	47
41	53
42	100
43	63
44	31
45	52
46	57
47	83
48	140
49	153
50	121
51	62
52	73
53	135
54	88
55	37
56	59
57	96
58	65
59	71
60	136
61	105
62	139
63	244
64	261
65	209
66	296

[1, 1, 2, 3, 5, 8, 7, 9, 10, 13, 23, 36, 29, 35, 64, 37, 39, 76, 77, 115, 192, 121, 17, 28, 31, 45, 46, 61, 107, 168, 149, 191, 340, 361, 189, 40, 31, 41, 72, 47, 53, 100, 63, 31, 52, 57, 83, 140, 153, 121, 62, 73, 135, 88, 37, 59, 96, 65, 71, 136, 105, 139, 244, 261, 209, 296]

cp's OEIS Frontend

A121369 a(1) = a(2) = 1, a(n) = A007947(a(n-1)) + A007947(a(n-2)) for n >= 3, i.e., a(n) is the largest squarefree divisor of a(n-1) plus the largest squarefree divisor of a(n-2).

Table of values

List of values

n	a(n)
1	1
2	1
3	2
4	3
5	5
6	8
7	7
8	9
9	10
10	13
11	23
12	36
13	29
14	35
15	64
16	37
17	39
18	76
19	77
20	115
21	192
22	121
23	17
24	28
25	31
26	45
27	46
28	61
29	107
30	168
31	149
32	191
33	340
34	361
35	189
36	40
37	31
38	41
39	72
40	47
41	53
42	100
43	63
44	31
45	52
46	57
47	83
48	140
49	153
50	121
51	62
52	73
53	135
54	88
55	37
56	59
57	96
58	65
59	71
60	136
61	105
62	139
63	244
64	261
65	209
66	296

n	a(n)
1	1
2	1
3	2
4	3
5	5
6	8
7	7
8	9
9	10
10	13
11	23
12	36
13	29
14	35
15	64
16	37
17	39
18	76
19	77
20	115
21	192
22	121
23	17
24	28
25	31
26	45
27	46
28	61
29	107
30	168
31	149
32	191
33	340
34	361
35	189
36	40
37	31
38	41
39	72
40	47
41	53
42	100
43	63
44	31
45	52
46	57
47	83
48	140
49	153
50	121
51	62
52	73
53	135
54	88
55	37
56	59
57	96
58	65
59	71
60	136
61	105
62	139
63	244
64	261
65	209
66	296

n	a(n)
1	1
2	1
3	2
4	3
5	5
6	8
7	7
8	9
9	10
10	13
11	23
12	36
13	29
14	35
15	64
16	37
17	39
18	76
19	77
20	115
21	192
22	121
23	17
24	28
25	31
26	45
27	46
28	61
29	107
30	168
31	149
32	191
33	340
34	361
35	189
36	40
37	31
38	41
39	72
40	47
41	53
42	100
43	63
44	31
45	52
46	57
47	83
48	140
49	153
50	121
51	62
52	73
53	135
54	88
55	37
56	59
57	96
58	65
59	71
60	136
61	105
62	139
63	244
64	261
65	209
66	296