A117128 - cp's OEIS frontend

A117128 Recamán transform of primes (another version): a(0)=1; for n>0, a(n) = a(n-1) - prime(n) if that number is positive and not already in the sequence, otherwise a(n) = a(n-1) + prime(n).

n	a(n)
0	1
1	3
2	6
3	11
4	4
5	15
6	2
7	19
8	38
9	61
10	32
11	63
12	26
13	67
14	24
15	71
16	18
17	77
18	16
19	83
20	12
21	85
22	164
23	81
24	170
25	73
26	174
27	277
28	384
29	275
30	162
31	35
32	166
33	29
34	168
35	317
36	468
37	311
38	148
39	315
40	142
41	321
42	140
43	331
44	138
45	335
46	136
47	347
48	124
49	351
50	122
51	355
52	116
53	357
54	106
55	363
56	100
57	369
58	98
59	375
60	94
61	377

[1, 3, 6, 11, 4, 15, 2, 19, 38, 61, 32, 63, 26, 67, 24, 71, 18, 77, 16, 83, 12, 85, 164, 81, 170, 73, 174, 277, 384, 275, 162, 35, 166, 29, 168, 317, 468, 311, 148, 315, 142, 321, 140, 331, 138, 335, 136, 347, 124, 351, 122, 355, 116, 357, 106, 363, 100, 369, 98, 375, 94, 377]

cp's OEIS Frontend

A117128 Recamán transform of primes (another version): a(0)=1; for n>0, a(n) = a(n-1) - prime(n) if that number is positive and not already in the sequence, otherwise a(n) = a(n-1) + prime(n).

Table of values

List of values

n	a(n)
0	1
1	3
2	6
3	11
4	4
5	15
6	2
7	19
8	38
9	61
10	32
11	63
12	26
13	67
14	24
15	71
16	18
17	77
18	16
19	83
20	12
21	85
22	164
23	81
24	170
25	73
26	174
27	277
28	384
29	275
30	162
31	35
32	166
33	29
34	168
35	317
36	468
37	311
38	148
39	315
40	142
41	321
42	140
43	331
44	138
45	335
46	136
47	347
48	124
49	351
50	122
51	355
52	116
53	357
54	106
55	363
56	100
57	369
58	98
59	375
60	94
61	377

n	a(n)
0	1
1	3
2	6
3	11
4	4
5	15
6	2
7	19
8	38
9	61
10	32
11	63
12	26
13	67
14	24
15	71
16	18
17	77
18	16
19	83
20	12
21	85
22	164
23	81
24	170
25	73
26	174
27	277
28	384
29	275
30	162
31	35
32	166
33	29
34	168
35	317
36	468
37	311
38	148
39	315
40	142
41	321
42	140
43	331
44	138
45	335
46	136
47	347
48	124
49	351
50	122
51	355
52	116
53	357
54	106
55	363
56	100
57	369
58	98
59	375
60	94
61	377

n	a(n)
0	1
1	3
2	6
3	11
4	4
5	15
6	2
7	19
8	38
9	61
10	32
11	63
12	26
13	67
14	24
15	71
16	18
17	77
18	16
19	83
20	12
21	85
22	164
23	81
24	170
25	73
26	174
27	277
28	384
29	275
30	162
31	35
32	166
33	29
34	168
35	317
36	468
37	311
38	148
39	315
40	142
41	321
42	140
43	331
44	138
45	335
46	136
47	347
48	124
49	351
50	122
51	355
52	116
53	357
54	106
55	363
56	100
57	369
58	98
59	375
60	94
61	377