A000028 - cp's OEIS frontend

A000028 Let k = p_1^e_1 p_2^e_2 p_3^e_3 ... be the prime factorization of n. Sequence gives k such that the sum of the numbers of 1's in the binary expansions of e_1, e_2, e_3, ... is odd.

n	a(n)
1	2
2	3
3	4
4	5
5	7
6	9
7	11
8	13
9	16
10	17
11	19
12	23
13	24
14	25
15	29
16	30
17	31
18	37
19	40
20	41
21	42
22	43
23	47
24	49
25	53
26	54
27	56
28	59
29	60
30	61
31	66
32	67
33	70
34	71
35	72
36	73
37	78
38	79
39	81
40	83
41	84
42	88
43	89
44	90
45	96
46	97
47	101
48	102
49	103
50	104
51	105
52	107
53	108
54	109
55	110
56	113
57	114
58	121
59	126
60	127
61	128
62	130
63	131
64	132
65	135
66	136
67	137

[2, 3, 4, 5, 7, 9, 11, 13, 16, 17, 19, 23, 24, 25, 29, 30, 31, 37, 40, 41, 42, 43, 47, 49, 53, 54, 56, 59, 60, 61, 66, 67, 70, 71, 72, 73, 78, 79, 81, 83, 84, 88, 89, 90, 96, 97, 101, 102, 103, 104, 105, 107, 108, 109, 110, 113, 114, 121, 126, 127, 128, 130, 131, 132, 135, 136, 137]

cp's OEIS Frontend

A000028 Let k = p_1^e_1 p_2^e_2 p_3^e_3 ... be the prime factorization of n. Sequence gives k such that the sum of the numbers of 1's in the binary expansions of e_1, e_2, e_3, ... is odd.

Table of values

List of values

n	a(n)
1	2
2	3
3	4
4	5
5	7
6	9
7	11
8	13
9	16
10	17
11	19
12	23
13	24
14	25
15	29
16	30
17	31
18	37
19	40
20	41
21	42
22	43
23	47
24	49
25	53
26	54
27	56
28	59
29	60
30	61
31	66
32	67
33	70
34	71
35	72
36	73
37	78
38	79
39	81
40	83
41	84
42	88
43	89
44	90
45	96
46	97
47	101
48	102
49	103
50	104
51	105
52	107
53	108
54	109
55	110
56	113
57	114
58	121
59	126
60	127
61	128
62	130
63	131
64	132
65	135
66	136
67	137

n	a(n)
1	2
2	3
3	4
4	5
5	7
6	9
7	11
8	13
9	16
10	17
11	19
12	23
13	24
14	25
15	29
16	30
17	31
18	37
19	40
20	41
21	42
22	43
23	47
24	49
25	53
26	54
27	56
28	59
29	60
30	61
31	66
32	67
33	70
34	71
35	72
36	73
37	78
38	79
39	81
40	83
41	84
42	88
43	89
44	90
45	96
46	97
47	101
48	102
49	103
50	104
51	105
52	107
53	108
54	109
55	110
56	113
57	114
58	121
59	126
60	127
61	128
62	130
63	131
64	132
65	135
66	136
67	137

n	a(n)
1	2
2	3
3	4
4	5
5	7
6	9
7	11
8	13
9	16
10	17
11	19
12	23
13	24
14	25
15	29
16	30
17	31
18	37
19	40
20	41
21	42
22	43
23	47
24	49
25	53
26	54
27	56
28	59
29	60
30	61
31	66
32	67
33	70
34	71
35	72
36	73
37	78
38	79
39	81
40	83
41	84
42	88
43	89
44	90
45	96
46	97
47	101
48	102
49	103
50	104
51	105
52	107
53	108
54	109
55	110
56	113
57	114
58	121
59	126
60	127
61	128
62	130
63	131
64	132
65	135
66	136
67	137