A090648 - cp's OEIS frontend

A090648 a(n)=2*(4^n-1)/denominator(B(2n)) where B(k) denotes the k-th Bernoulli number.

n	a(n)
0	0
1	1
2	1
3	3
4	17
5	31
6	3
7	5461
8	257
9	657
10	6355
11	60787
12	12291
13	22369621
14	617093
15	149943
16	16843009
17	5726623061
18	71613
19	91625968981
20	162529435
21	4870483401
22	50991843607
23	499069107643
24	12129927891
25	34118178995231
26	5664905191661
27	45148868444817
28	165649641466501

[0, 1, 1, 3, 17, 31, 3, 5461, 257, 657, 6355, 60787, 12291, 22369621, 617093, 149943, 16843009, 5726623061, 71613, 91625968981, 162529435, 4870483401, 50991843607, 499069107643, 12129927891, 34118178995231, 5664905191661, 45148868444817, 165649641466501]

cp's OEIS Frontend

A090648 a(n)=2*(4^n-1)/denominator(B(2n)) where B(k) denotes the k-th Bernoulli number.

Table of values

List of values