A286559 - cp's OEIS frontend

A286559 Compound filter (the left & right summand of Hofstadter Q-sequence): a(n) = P(Q(n-Q(n-1)), Q(n-Q(n-2))), where P(n,k) is sequence A000027 used as a pairing function, with a(1) = a(2) = 0.

n	a(n)
1	0
2	0
3	1
4	2
5	2
6	5
7	8
8	8
9	13
10	13
11	13
12	25
13	24
14	25
15	41
16	32
17	41
18	50
19	50
20	61
21	61
22	61
23	61
24	113
25	84
26	86
27	113
28	113
29	113
30	113
31	181
32	128
33	129
34	181
35	200
36	163
37	182
38	221
39	200
40	221
41	242
42	242
43	265
44	265
45	265
46	265
47	265
48	481
49	263
50	290
51	420
52	363
53	314
54	422
55	420
56	365
57	481
58	420
59	481
60	481
61	481
62	481
63	761
64	512
65	452
66	687
67	577
68	513
69	722
70	761
71	650
72	687
73	762
74	723
75	760
76	722
77	842
78	760
79	801

[0, 0, 1, 2, 2, 5, 8, 8, 13, 13, 13, 25, 24, 25, 41, 32, 41, 50, 50, 61, 61, 61, 61, 113, 84, 86, 113, 113, 113, 113, 181, 128, 129, 181, 200, 163, 182, 221, 200, 221, 242, 242, 265, 265, 265, 265, 265, 481, 263, 290, 420, 363, 314, 422, 420, 365, 481, 420, 481, 481, 481, 481, 761, 512, 452, 687, 577, 513, 722, 761, 650, 687, 762, 723, 760, 722, 842, 760, 801]

cp's OEIS Frontend

A286559 Compound filter (the left & right summand of Hofstadter Q-sequence): a(n) = P(Q(n-Q(n-1)), Q(n-Q(n-2))), where P(n,k) is sequence A000027 used as a pairing function, with a(1) = a(2) = 0.

Table of values

List of values

n	a(n)
1	0
2	0
3	1
4	2
5	2
6	5
7	8
8	8
9	13
10	13
11	13
12	25
13	24
14	25
15	41
16	32
17	41
18	50
19	50
20	61
21	61
22	61
23	61
24	113
25	84
26	86
27	113
28	113
29	113
30	113
31	181
32	128
33	129
34	181
35	200
36	163
37	182
38	221
39	200
40	221
41	242
42	242
43	265
44	265
45	265
46	265
47	265
48	481
49	263
50	290
51	420
52	363
53	314
54	422
55	420
56	365
57	481
58	420
59	481
60	481
61	481
62	481
63	761
64	512
65	452
66	687
67	577
68	513
69	722
70	761
71	650
72	687
73	762
74	723
75	760
76	722
77	842
78	760
79	801

n	a(n)
1	0
2	0
3	1
4	2
5	2
6	5
7	8
8	8
9	13
10	13
11	13
12	25
13	24
14	25
15	41
16	32
17	41
18	50
19	50
20	61
21	61
22	61
23	61
24	113
25	84
26	86
27	113
28	113
29	113
30	113
31	181
32	128
33	129
34	181
35	200
36	163
37	182
38	221
39	200
40	221
41	242
42	242
43	265
44	265
45	265
46	265
47	265
48	481
49	263
50	290
51	420
52	363
53	314
54	422
55	420
56	365
57	481
58	420
59	481
60	481
61	481
62	481
63	761
64	512
65	452
66	687
67	577
68	513
69	722
70	761
71	650
72	687
73	762
74	723
75	760
76	722
77	842
78	760
79	801

n	a(n)
1	0
2	0
3	1
4	2
5	2
6	5
7	8
8	8
9	13
10	13
11	13
12	25
13	24
14	25
15	41
16	32
17	41
18	50
19	50
20	61
21	61
22	61
23	61
24	113
25	84
26	86
27	113
28	113
29	113
30	113
31	181
32	128
33	129
34	181
35	200
36	163
37	182
38	221
39	200
40	221
41	242
42	242
43	265
44	265
45	265
46	265
47	265
48	481
49	263
50	290
51	420
52	363
53	314
54	422
55	420
56	365
57	481
58	420
59	481
60	481
61	481
62	481
63	761
64	512
65	452
66	687
67	577
68	513
69	722
70	761
71	650
72	687
73	762
74	723
75	760
76	722
77	842
78	760
79	801