A225314 - cp's OEIS frontend

A225314 Number of 7Xn -1,1 arrays such that the sum over i=1..7,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 7 positions 1..n distance from the hinge of a south-pointing gate without turning the gate).

n	a(n)
1	8
2	87
3	474
4	1787
5	5304
6	13333
7	29638
8	60007
9	112790
10	199669
11	336342
12	543465
13	847456
14	1281681
15	1887330
16	2714817
17	3824812
18	5289809
19	7195252
20	9641399
21	12744472
22	16638757
23	21477906
24	27437211
25	34714980
26	43535143
27	54148610
28	66836145
29	81909858

[8, 87, 474, 1787, 5304, 13333, 29638, 60007, 112790, 199669, 336342, 543465, 847456, 1281681, 1887330, 2714817, 3824812, 5289809, 7195252, 9641399, 12744472, 16638757, 21477906, 27437211, 34714980, 43535143, 54148610, 66836145, 81909858]

cp's OEIS Frontend

A225314 Number of 7Xn -1,1 arrays such that the sum over i=1..7,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 7 positions 1..n distance from the hinge of a south-pointing gate without turning the gate).

Table of values

List of values