A000779 - cp's OEIS frontend

A000779 a(n) = 2(2n-1)!!-(n-1)!2^(n-1), where (2n-1)!! is A001147(n).

n	a(n)
1	1
2	4
3	22
4	162
5	1506
6	16950
7	224190
8	3408930
9	58596930
10	1123663590
11	23782729950
12	550718680050
13	13849716607650
14	375904338960150
15	10952237584237950
16	340947694234397250
17	11294123783425733250
18	396665528378000631750

[1, 4, 22, 162, 1506, 16950, 224190, 3408930, 58596930, 1123663590, 23782729950, 550718680050, 13849716607650, 375904338960150, 10952237584237950, 340947694234397250, 11294123783425733250, 396665528378000631750]

cp's OEIS Frontend

A000779 a(n) = 2(2n-1)!!-(n-1)!2^(n-1), where (2n-1)!! is A001147(n).

Table of values

List of values

cp's OEIS Frontend

A000779 a(n) = 2*(2n-1)!!-(n-1)!*2^(n-1), where (2n-1)!! is A001147(n).

Table of values

List of values

A000779 a(n) = 2(2n-1)!!-(n-1)!2^(n-1), where (2n-1)!! is A001147(n).