A261273 - cp's OEIS frontend

A261273 Take the list of positive rationals {R(n): n>=1} in the order defined by Calkin and Wilf (Recounting the Rationals, 1999); a(n) = denominator of R(prime(n)).

n	a(n)
1	2
2	1
3	2
4	1
5	2
6	3
7	4
8	3
9	2
10	4
11	1
12	7
13	8
14	5
15	2
16	8
17	4
18	5
19	5
20	4
21	11
22	3
23	8
24	12
25	9
26	12
27	5
28	8
29	11
30	10
31	1
32	6
33	14
34	9
35	18
36	7
37	13
38	11
39	8
40	18
41	12
42	19
43	2
44	11
45	16
46	7
47	13
48	3
49	10
50	17
51	18
52	4
53	13
54	6
55	8
56	6
57	16
58	5
59	23
60	22
61	13
62	26
63	17
64	10
65	23
66	16
67	19
68	29
69	18
70	23
71	22
72	12
73	7
74	25
75	11
76	2
77	20
78	23
79	26
80	29
81	18
82	31
83	8
84	27
85	11
86	14
87	16
88	27
89	24
90	7
91	18
92	4
93	9
94	14
95	11
96	6
97	8
98	20
99	13
100	21
101	19
102	32
103	22
104	30
105	17
106	23
107	26
108	40
109	18
110	43
111	7
112	41
113	44
114	27
115	13
116	20
117	17
118	14
119	36
120	30
121	49
122	37
123	50
124	34
125	31
126	28
127	39
128	12
129	19
130	33
131	23
132	16
133	9
134	31
135	24
136	15
137	24
138	25
139	30
140	50
141	31
142	46
143	17
144	22
145	27
146	18
147	55
148	50
149	29
150	8
151	41
152	36
153	25
154	14
155	23
156	10
157	17
158	32
159	47
160	40
161	26
162	34
163	13
164	22
165	32
166	14
167	5
168	27

[2, 1, 2, 1, 2, 3, 4, 3, 2, 4, 1, 7, 8, 5, 2, 8, 4, 5, 5, 4, 11, 3, 8, 12, 9, 12, 5, 8, 11, 10, 1, 6, 14, 9, 18, 7, 13, 11, 8, 18, 12, 19, 2, 11, 16, 7, 13, 3, 10, 17, 18, 4, 13, 6, 8, 6, 16, 5, 23, 22, 13, 26, 17, 10, 23, 16, 19, 29, 18, 23, 22, 12, 7, 25, 11, 2, 20, 23, 26, 29, 18, 31, 8, 27, 11, 14, 16, 27, 24, 7, 18, 4, 9, 14, 11, 6, 8, 20, 13, 21, 19, 32, 22, 30, 17, 23, 26, 40, 18, 43, 7, 41, 44, 27, 13, 20, 17, 14, 36, 30, 49, 37, 50, 34, 31, 28, 39, 12, 19, 33, 23, 16, 9, 31, 24, 15, 24, 25, 30, 50, 31, 46, 17, 22, 27, 18, 55, 50, 29, 8, 41, 36, 25, 14, 23, 10, 17, 32, 47, 40, 26, 34, 13, 22, 32, 14, 5, 27]

cp's OEIS Frontend

A261273 Take the list of positive rationals {R(n): n>=1} in the order defined by Calkin and Wilf (Recounting the Rationals, 1999); a(n) = denominator of R(prime(n)).

Table of values

List of values

n	a(n)
1	2
2	1
3	2
4	1
5	2
6	3
7	4
8	3
9	2
10	4
11	1
12	7
13	8
14	5
15	2
16	8
17	4
18	5
19	5
20	4
21	11
22	3
23	8
24	12
25	9
26	12
27	5
28	8
29	11
30	10
31	1
32	6
33	14
34	9
35	18
36	7
37	13
38	11
39	8
40	18
41	12
42	19
43	2
44	11
45	16
46	7
47	13
48	3
49	10
50	17
51	18
52	4
53	13
54	6
55	8
56	6
57	16
58	5
59	23
60	22
61	13
62	26
63	17
64	10
65	23
66	16
67	19
68	29
69	18
70	23
71	22
72	12
73	7
74	25
75	11
76	2
77	20
78	23
79	26
80	29
81	18
82	31
83	8
84	27
85	11
86	14
87	16
88	27
89	24
90	7
91	18
92	4
93	9
94	14
95	11
96	6
97	8
98	20
99	13
100	21
101	19
102	32
103	22
104	30
105	17
106	23
107	26
108	40
109	18
110	43
111	7
112	41
113	44
114	27
115	13
116	20
117	17
118	14
119	36
120	30
121	49
122	37
123	50
124	34
125	31
126	28
127	39
128	12
129	19
130	33
131	23
132	16
133	9
134	31
135	24
136	15
137	24
138	25
139	30
140	50
141	31
142	46
143	17
144	22
145	27
146	18
147	55
148	50
149	29
150	8
151	41
152	36
153	25
154	14
155	23
156	10
157	17
158	32
159	47
160	40
161	26
162	34
163	13
164	22
165	32
166	14
167	5
168	27

n	a(n)
1	2
2	1
3	2
4	1
5	2
6	3
7	4
8	3
9	2
10	4
11	1
12	7
13	8
14	5
15	2
16	8
17	4
18	5
19	5
20	4
21	11
22	3
23	8
24	12
25	9
26	12
27	5
28	8
29	11
30	10
31	1
32	6
33	14
34	9
35	18
36	7
37	13
38	11
39	8
40	18
41	12
42	19
43	2
44	11
45	16
46	7
47	13
48	3
49	10
50	17
51	18
52	4
53	13
54	6
55	8
56	6
57	16
58	5
59	23
60	22
61	13
62	26
63	17
64	10
65	23
66	16
67	19
68	29
69	18
70	23
71	22
72	12
73	7
74	25
75	11
76	2
77	20
78	23
79	26
80	29
81	18
82	31
83	8
84	27
85	11
86	14
87	16
88	27
89	24
90	7
91	18
92	4
93	9
94	14
95	11
96	6
97	8
98	20
99	13
100	21
101	19
102	32
103	22
104	30
105	17
106	23
107	26
108	40
109	18
110	43
111	7
112	41
113	44
114	27
115	13
116	20
117	17
118	14
119	36
120	30
121	49
122	37
123	50
124	34
125	31
126	28
127	39
128	12
129	19
130	33
131	23
132	16
133	9
134	31
135	24
136	15
137	24
138	25
139	30
140	50
141	31
142	46
143	17
144	22
145	27
146	18
147	55
148	50
149	29
150	8
151	41
152	36
153	25
154	14
155	23
156	10
157	17
158	32
159	47
160	40
161	26
162	34
163	13
164	22
165	32
166	14
167	5
168	27

n	a(n)
1	2
2	1
3	2
4	1
5	2
6	3
7	4
8	3
9	2
10	4
11	1
12	7
13	8
14	5
15	2
16	8
17	4
18	5
19	5
20	4
21	11
22	3
23	8
24	12
25	9
26	12
27	5
28	8
29	11
30	10
31	1
32	6
33	14
34	9
35	18
36	7
37	13
38	11
39	8
40	18
41	12
42	19
43	2
44	11
45	16
46	7
47	13
48	3
49	10
50	17
51	18
52	4
53	13
54	6
55	8
56	6
57	16
58	5
59	23
60	22
61	13
62	26
63	17
64	10
65	23
66	16
67	19
68	29
69	18
70	23
71	22
72	12
73	7
74	25
75	11
76	2
77	20
78	23
79	26
80	29
81	18
82	31
83	8
84	27
85	11
86	14
87	16
88	27
89	24
90	7
91	18
92	4
93	9
94	14
95	11
96	6
97	8
98	20
99	13
100	21
101	19
102	32
103	22
104	30
105	17
106	23
107	26
108	40
109	18
110	43
111	7
112	41
113	44
114	27
115	13
116	20
117	17
118	14
119	36
120	30
121	49
122	37
123	50
124	34
125	31
126	28
127	39
128	12
129	19
130	33
131	23
132	16
133	9
134	31
135	24
136	15
137	24
138	25
139	30
140	50
141	31
142	46
143	17
144	22
145	27
146	18
147	55
148	50
149	29
150	8
151	41
152	36
153	25
154	14
155	23
156	10
157	17
158	32
159	47
160	40
161	26
162	34
163	13
164	22
165	32
166	14
167	5
168	27