A034094 - cp's OEIS frontend

A034094 (-1)sigma perfect numbers: (-1)sigma(a) = m*a for some integer m, where if a = Product p(i)^r(i) then (-1)sigma(a) = Product_{i} (-1 + Sum_{s=1..r(i)} p(i)^s).

n	a(n)
1	1
2	20
3	312
4	9744
5	29280
6	53352
7	1666224
8	5006880
9	106798080
10	133301760
11	980733600
12	9099742080
13	18262471680
14	22794600960
15	1556055895680
16	3577201689600
17	4464942451200
18	380428773854896765462278360268800000

[1, 20, 312, 9744, 29280, 53352, 1666224, 5006880, 106798080, 133301760, 980733600, 9099742080, 18262471680, 22794600960, 1556055895680, 3577201689600, 4464942451200, 380428773854896765462278360268800000]

cp's OEIS Frontend

A034094 (-1)sigma perfect numbers: (-1)sigma(a) = m*a for some integer m, where if a = Product p(i)^r(i) then (-1)sigma(a) = Product_{i} (-1 + Sum_{s=1..r(i)} p(i)^s).

Table of values

List of values