A307353 - cp's OEIS frontend

A307353 a(n) = Sum_{1<=i<=j<=k<=n} (i+j+k)!/(i!j!k!).

n	a(n)
0	0
1	6
2	138
3	2808
4	59083
5	1298797
6	29538183
7	688783509
8	16365391557
9	394523905488
10	9621386549905
11	236859066714283
12	5876752842394018
13	146774130963028054
14	3686474939155802036
15	93044751867415156290
16	2358431594463240429469

[0, 6, 138, 2808, 59083, 1298797, 29538183, 688783509, 16365391557, 394523905488, 9621386549905, 236859066714283, 5876752842394018, 146774130963028054, 3686474939155802036, 93044751867415156290, 2358431594463240429469]

cp's OEIS Frontend

A307353 a(n) = Sum_{1<=i<=j<=k<=n} (i+j+k)!/(i!j!k!).

Table of values

List of values

cp's OEIS Frontend

A307353 a(n) = Sum_{1<=i<=j<=k<=n} (i+j+k)!/(i!*j!*k!).

Table of values

List of values

A307353 a(n) = Sum_{1<=i<=j<=k<=n} (i+j+k)!/(i!j!k!).