A225068    Least octagonal (8-gonal) number that is the product of n octagonal numbers greater than 1.

8, 1408, 2165800, 37333296, 19384601600, 69370076160, 69370076160, 56288711711232000, 7917914554368000000, 199449790781142859776

1	8
2	1408
3	2165800
4	37333296
5	19384601600
6	69370076160
7	69370076160
8	56288711711232000
9	7917914554368000000
10	199449790781142859776


a(1) = 8 = oct(2) = oct(2)
Indices: 2
Values:  8

a(2) = 1408 = oct(22) = oct(2) * oct(8)
Indices: 2,8
Values:  8,176

a(3) = 2165800 = oct(850) = oct(4) * oct(5) * oct(17)
Indices: 4,5,17
Values:  40,65,833

a(4) = 37333296 = oct(3528) = oct(3)^2 * oct(8) * oct(13)
Indices: 3,3,8,13
Values:  21,21,176,481

a(5) = 19384601600 = oct(80384) = oct(2)^2 * oct(5) * oct(14) * oct(53)
Indices: 2,2,5,14,53
Values:  8,8,65,560,8321

a(6) = 69370076160 = oct(152064) = oct(3)^3 * oct(4) * oct(7) * oct(22)
Indices: 3,3,3,4,7,22
Values:  21,21,21,40,133,1408

a(7) = 69370076160 = oct(152064) = oct(2) * oct(3)^3 * oct(4) * oct(7) * oct(8)
Indices: 2,3,3,3,4,7,8
Values:  8,21,21,21,40,133,176

a(8) = 56288711711232000 = oct(136977750) = oct(2)^4 * oct(3) * oct(13) * oct(75) * oct(165)
Indices: 2,2,2,2,3,13,75,165
Values:  8,8,8,8,21,481,16725,81345

a(9) = 7917914554368000000 = oct(1624593750) = oct(2)^2 * oct(4)^3 * oct(5) * oct(14) * oct(15) * oct(166)
Indices: 2,2,4,4,4,5,14,15,166
Values:  8,8,40,40,40,65,560,645,82336

a(10) = 199449790781142859776 = oct(8153726976) = oct(2)^4 * oct(3) * oct(6)^2 * oct(13) * oct(61) * oct(126)
Indices: 2,2,2,2,3,6,6,13,61,126
Values:  8,8,8,8,21,96,96,481,11041,47376