A338811 - cp's OEIS frontend

A338811 a(n) = (n!/6) * Sum_{i,j,k > 0 and i+j+k=n} d(i)d(j)d(k)/(ijk), where d(n) is the number of divisors of n.

n	a(n)
1	0
2	0
3	1
4	12
5	100
6	870
7	7588
8	73808
9	764524
10	8448120
11	103816944
12	1334764728
13	18483356736
14	274780501632
15	4371694872192
16	71815113008640
17	1282261138007040
18	23828058693642240
19	468231649812725760
20	9599857257164820480
21	205863214718290636800
22	4646428416182168985600

[0, 0, 1, 12, 100, 870, 7588, 73808, 764524, 8448120, 103816944, 1334764728, 18483356736, 274780501632, 4371694872192, 71815113008640, 1282261138007040, 23828058693642240, 468231649812725760, 9599857257164820480, 205863214718290636800, 4646428416182168985600]

cp's OEIS Frontend

A338811 a(n) = (n!/6) * Sum_{i,j,k > 0 and i+j+k=n} d(i)d(j)d(k)/(ijk), where d(n) is the number of divisors of n.

Table of values

List of values

cp's OEIS Frontend

A338811 a(n) = (n!/6) * Sum_{i,j,k > 0 and i+j+k=n} d(i)*d(j)*d(k)/(i*j*k), where d(n) is the number of divisors of n.

Table of values

List of values

A338811 a(n) = (n!/6) * Sum_{i,j,k > 0 and i+j+k=n} d(i)d(j)d(k)/(ijk), where d(n) is the number of divisors of n.