A193538 - cp's OEIS frontend

A193538 O.g.f.: exp( Sum_{n>=1} (sigma(2n)-sigma(n))^2/2 x^n/n ).

n	a(n)
0	1
1	2
2	6
3	20
4	46
5	116
6	284
7	632
8	1414
9	3102
10	6536
11	13636
12	28020
13	56300
14	111888
15	219608
16	424694
17	813104
18	1540818
19	2888060
20	5366072
21	9884616
22	18050428
23	32713048
24	58851972
25	105113942
26	186505864
27	328821408
28	576153008
29	1003687444
30	1738735728
31	2995837872

[1, 2, 6, 20, 46, 116, 284, 632, 1414, 3102, 6536, 13636, 28020, 56300, 111888, 219608, 424694, 813104, 1540818, 2888060, 5366072, 9884616, 18050428, 32713048, 58851972, 105113942, 186505864, 328821408, 576153008, 1003687444, 1738735728, 2995837872]

cp's OEIS Frontend

A193538 O.g.f.: exp( Sum_{n>=1} (sigma(2n)-sigma(n))^2/2 x^n/n ).

Table of values

List of values

cp's OEIS Frontend

A193538 O.g.f.: exp( Sum_{n>=1} (sigma(2*n)-sigma(n))^2/2 * x^n/n ).

Table of values

List of values

A193538 O.g.f.: exp( Sum_{n>=1} (sigma(2n)-sigma(n))^2/2 x^n/n ).