A225315 - cp's OEIS frontend

A225315 Number of 8Xn -1,1 arrays such that the sum over i=1..8,j=1..n of i*x(i,j) is zero and rows are nondecreasing (ways to put n thrusters pointing east or west at each of 8 positions 1..n distance from the hinge of a south-pointing gate without turning the gate).

n	a(n)
1	14
2	217
3	1576
4	7445
5	26498
6	77721
7	197440
8	449693
9	939130
10	1828785
11	3360554
12	5882479
13	9878430
14	16007047
15	25142264
16	38426053
17	57321356
18	83680907
19	119814040
20	168573865
21	233439470
22	318623729
23	429172318
24	571094583
25	751480676
26	978657917

[14, 217, 1576, 7445, 26498, 77721, 197440, 449693, 939130, 1828785, 3360554, 5882479, 9878430, 16007047, 25142264, 38426053, 57321356, 83680907, 119814040, 168573865, 233439470, 318623729, 429172318, 571094583, 751480676, 978657917]

cp's OEIS Frontend

A225315 Number of 8Xn -1,1 arrays such that the sum over i=1..8,j=1..n of i*x(i,j) is zero and rows are nondecreasing (ways to put n thrusters pointing east or west at each of 8 positions 1..n distance from the hinge of a south-pointing gate without turning the gate).

Table of values

List of values