A015509 - cp's OEIS frontend

A015509 a(1) = 1, a(n) = Sum_{k=1..n-1} ((8^k - 1)/7)*a(k).

n	a(n)
1	1
2	1
3	10
4	740
5	433640
6	2030302480
7	76034827876000
8	22779578222682344000
9	54596862986901017252624000
10	1046838176230046602563156976288000
11	160576277008444677145920980328106246720000

[1, 1, 10, 740, 433640, 2030302480, 76034827876000, 22779578222682344000, 54596862986901017252624000, 1046838176230046602563156976288000, 160576277008444677145920980328106246720000]

cp's OEIS Frontend

A015509 a(1) = 1, a(n) = Sum_{k=1..n-1} ((8^k - 1)/7)*a(k).

Table of values

List of values