A330572 - cp's OEIS frontend

A330572 a(n) = Sum_{k = 1..n} [u_2(k)u_2(n+1-k)], where u_2(k) is the number of unordered factorizations k = ij (A038548).

n	a(n)
0	0
1	1
2	2
3	3
4	6
5	7
6	10
7	12
8	14
9	19
10	20
11	24
12	28
13	31
14	32
15	40
16	40
17	48
18	48
19	56
20	56
21	67
22	60
23	77
24	72
25	85
26	80
27	98
28	88
29	108
30	98
31	117
32	110
33	131
34	110
35	147
36	128
37	149
38	140
39	169
40	144
41	182
42	154
43	192
44	174
45	205
46	168
47	228
48	188
49	226
50	208
51	250
52	204
53	268
54	218
55	273
56	246
57	285
58	234
59	324

[0, 1, 2, 3, 6, 7, 10, 12, 14, 19, 20, 24, 28, 31, 32, 40, 40, 48, 48, 56, 56, 67, 60, 77, 72, 85, 80, 98, 88, 108, 98, 117, 110, 131, 110, 147, 128, 149, 140, 169, 144, 182, 154, 192, 174, 205, 168, 228, 188, 226, 208, 250, 204, 268, 218, 273, 246, 285, 234, 324]

cp's OEIS Frontend

A330572 a(n) = Sum_{k = 1..n} [u_2(k)u_2(n+1-k)], where u_2(k) is the number of unordered factorizations k = ij (A038548).

Table of values

List of values

n	a(n)
0	0
1	1
2	2
3	3
4	6
5	7
6	10
7	12
8	14
9	19
10	20
11	24
12	28
13	31
14	32
15	40
16	40
17	48
18	48
19	56
20	56
21	67
22	60
23	77
24	72
25	85
26	80
27	98
28	88
29	108
30	98
31	117
32	110
33	131
34	110
35	147
36	128
37	149
38	140
39	169
40	144
41	182
42	154
43	192
44	174
45	205
46	168
47	228
48	188
49	226
50	208
51	250
52	204
53	268
54	218
55	273
56	246
57	285
58	234
59	324

n	a(n)
0	0
1	1
2	2
3	3
4	6
5	7
6	10
7	12
8	14
9	19
10	20
11	24
12	28
13	31
14	32
15	40
16	40
17	48
18	48
19	56
20	56
21	67
22	60
23	77
24	72
25	85
26	80
27	98
28	88
29	108
30	98
31	117
32	110
33	131
34	110
35	147
36	128
37	149
38	140
39	169
40	144
41	182
42	154
43	192
44	174
45	205
46	168
47	228
48	188
49	226
50	208
51	250
52	204
53	268
54	218
55	273
56	246
57	285
58	234
59	324

cp's OEIS Frontend

A330572 a(n) = Sum_{k = 1..n} [u_2(k)*u_2(n+1-k)], where u_2(k) is the number of unordered factorizations k = i*j (A038548).

Table of values

List of values

A330572 a(n) = Sum_{k = 1..n} [u_2(k)u_2(n+1-k)], where u_2(k) is the number of unordered factorizations k = ij (A038548).

n	a(n)
0	0
1	1
2	2
3	3
4	6
5	7
6	10
7	12
8	14
9	19
10	20
11	24
12	28
13	31
14	32
15	40
16	40
17	48
18	48
19	56
20	56
21	67
22	60
23	77
24	72
25	85
26	80
27	98
28	88
29	108
30	98
31	117
32	110
33	131
34	110
35	147
36	128
37	149
38	140
39	169
40	144
41	182
42	154
43	192
44	174
45	205
46	168
47	228
48	188
49	226
50	208
51	250
52	204
53	268
54	218
55	273
56	246
57	285
58	234
59	324