A252280 - cp's OEIS frontend

A252280 For a prime p, denote by s(p,k) the odd part of the digital sum of p^k. Let k_1 be the smallest k such that s(p,k) is divisible by 7. Sequence lists primes p for which s(p,k_1)=7.

n	a(n)
1	2
2	5
3	7
4	11
5	19
6	29
7	31
8	37
9	41
10	43
11	59
12	61
13	71
14	73
15	79
16	97
17	101
18	103
19	107
20	109
21	127
22	137
23	149
24	151
25	163
26	167
27	181
28	193
29	197
30	211
31	223
32	233
33	239
34	241
35	257
36	271
37	277
38	293
39	307
40	313
41	331
42	347
43	359
44	373
45	383
46	397
47	409
48	419
49	421
50	431
51	433
52	467
53	487
54	491
55	509
56	523

[2, 5, 7, 11, 19, 29, 31, 37, 41, 43, 59, 61, 71, 73, 79, 97, 101, 103, 107, 109, 127, 137, 149, 151, 163, 167, 181, 193, 197, 211, 223, 233, 239, 241, 257, 271, 277, 293, 307, 313, 331, 347, 359, 373, 383, 397, 409, 419, 421, 431, 433, 467, 487, 491, 509, 523]

cp's OEIS Frontend

A252280 For a prime p, denote by s(p,k) the odd part of the digital sum of p^k. Let k_1 be the smallest k such that s(p,k) is divisible by 7. Sequence lists primes p for which s(p,k_1)=7.

Table of values

List of values

n	a(n)
1	2
2	5
3	7
4	11
5	19
6	29
7	31
8	37
9	41
10	43
11	59
12	61
13	71
14	73
15	79
16	97
17	101
18	103
19	107
20	109
21	127
22	137
23	149
24	151
25	163
26	167
27	181
28	193
29	197
30	211
31	223
32	233
33	239
34	241
35	257
36	271
37	277
38	293
39	307
40	313
41	331
42	347
43	359
44	373
45	383
46	397
47	409
48	419
49	421
50	431
51	433
52	467
53	487
54	491
55	509
56	523

n	a(n)
1	2
2	5
3	7
4	11
5	19
6	29
7	31
8	37
9	41
10	43
11	59
12	61
13	71
14	73
15	79
16	97
17	101
18	103
19	107
20	109
21	127
22	137
23	149
24	151
25	163
26	167
27	181
28	193
29	197
30	211
31	223
32	233
33	239
34	241
35	257
36	271
37	277
38	293
39	307
40	313
41	331
42	347
43	359
44	373
45	383
46	397
47	409
48	419
49	421
50	431
51	433
52	467
53	487
54	491
55	509
56	523

n	a(n)
1	2
2	5
3	7
4	11
5	19
6	29
7	31
8	37
9	41
10	43
11	59
12	61
13	71
14	73
15	79
16	97
17	101
18	103
19	107
20	109
21	127
22	137
23	149
24	151
25	163
26	167
27	181
28	193
29	197
30	211
31	223
32	233
33	239
34	241
35	257
36	271
37	277
38	293
39	307
40	313
41	331
42	347
43	359
44	373
45	383
46	397
47	409
48	419
49	421
50	431
51	433
52	467
53	487
54	491
55	509
56	523