A274648 - cp's OEIS frontend

A274648 A variation on Recamán's sequence (A005132): a(n) is the first positive number of the form a(n-1)-nk, k>0 not already in the sequence; and if no such number exists, then a(n) is the first number of the form a(n-1)+nk, k>0 not already in the sequence.

n	a(n)
0	0
1	1
2	3
3	6
4	2
5	7
6	13
7	20
8	12
9	21
10	11
11	22
12	10
13	23
14	9
15	24
16	8
17	25
18	43
19	5
20	45
21	66
22	44
23	67
24	19
25	69
26	17
27	71
28	15
29	73
30	103
31	72
32	40
33	106
34	38
35	108
36	36
37	110
38	34
39	112
40	32
41	114
42	30
43	116
44	28
45	118
46	26
47	120
48	168
49	119
50	169
51	16
52	68
53	121
54	175
55	65
56	177
57	63
58	179
59	61
60	181
61	59
62	183

[0, 1, 3, 6, 2, 7, 13, 20, 12, 21, 11, 22, 10, 23, 9, 24, 8, 25, 43, 5, 45, 66, 44, 67, 19, 69, 17, 71, 15, 73, 103, 72, 40, 106, 38, 108, 36, 110, 34, 112, 32, 114, 30, 116, 28, 118, 26, 120, 168, 119, 169, 16, 68, 121, 175, 65, 177, 63, 179, 61, 181, 59, 183]

cp's OEIS Frontend

A274648 A variation on Recamán's sequence (A005132): a(n) is the first positive number of the form a(n-1)-nk, k>0 not already in the sequence; and if no such number exists, then a(n) is the first number of the form a(n-1)+nk, k>0 not already in the sequence.

Table of values

List of values

n	a(n)
0	0
1	1
2	3
3	6
4	2
5	7
6	13
7	20
8	12
9	21
10	11
11	22
12	10
13	23
14	9
15	24
16	8
17	25
18	43
19	5
20	45
21	66
22	44
23	67
24	19
25	69
26	17
27	71
28	15
29	73
30	103
31	72
32	40
33	106
34	38
35	108
36	36
37	110
38	34
39	112
40	32
41	114
42	30
43	116
44	28
45	118
46	26
47	120
48	168
49	119
50	169
51	16
52	68
53	121
54	175
55	65
56	177
57	63
58	179
59	61
60	181
61	59
62	183

n	a(n)
0	0
1	1
2	3
3	6
4	2
5	7
6	13
7	20
8	12
9	21
10	11
11	22
12	10
13	23
14	9
15	24
16	8
17	25
18	43
19	5
20	45
21	66
22	44
23	67
24	19
25	69
26	17
27	71
28	15
29	73
30	103
31	72
32	40
33	106
34	38
35	108
36	36
37	110
38	34
39	112
40	32
41	114
42	30
43	116
44	28
45	118
46	26
47	120
48	168
49	119
50	169
51	16
52	68
53	121
54	175
55	65
56	177
57	63
58	179
59	61
60	181
61	59
62	183

cp's OEIS Frontend

A274648 A variation on Recamán's sequence (A005132): a(n) is the first positive number of the form a(n-1)-n*k, k>0 not already in the sequence; and if no such number exists, then a(n) is the first number of the form a(n-1)+n*k, k>0 not already in the sequence.

Table of values

List of values

A274648 A variation on Recamán's sequence (A005132): a(n) is the first positive number of the form a(n-1)-nk, k>0 not already in the sequence; and if no such number exists, then a(n) is the first number of the form a(n-1)+nk, k>0 not already in the sequence.

n	a(n)
0	0
1	1
2	3
3	6
4	2
5	7
6	13
7	20
8	12
9	21
10	11
11	22
12	10
13	23
14	9
15	24
16	8
17	25
18	43
19	5
20	45
21	66
22	44
23	67
24	19
25	69
26	17
27	71
28	15
29	73
30	103
31	72
32	40
33	106
34	38
35	108
36	36
37	110
38	34
39	112
40	32
41	114
42	30
43	116
44	28
45	118
46	26
47	120
48	168
49	119
50	169
51	16
52	68
53	121
54	175
55	65
56	177
57	63
58	179
59	61
60	181
61	59
62	183