A225347 - cp's OEIS frontend

A225347 Number of 7Xn -1,1 arrays such that the sum over i=1..7,j=1..n of i*x(i,j) is zero, the sum of x(i,j) is zero, and rows are nondecreasing (number of ways to distribute n-across galley oarsmen left-right at 7 fore-aft positions so that there are no turning moments on the ship).

n	a(n)
1	0
2	33
3	0
4	395
5	0
6	2073
7	0
8	7261
9	0
10	19709
11	0
12	45385
13	0
14	92673
15	0
16	173189
17	0
18	301799
19	0
20	497661
21	0
22	783969
23	0
24	1189311
25	0
26	1747059
27	0
28	2497109
29	0
30	3484867
31	0
32	4763439
33	0
34	6392095
35	0
36	8439027
37	0
38	10979255
39	0
40	14097919
41	0
42	17887629
43	0
44	22452391
45	0

[0, 33, 0, 395, 0, 2073, 0, 7261, 0, 19709, 0, 45385, 0, 92673, 0, 173189, 0, 301799, 0, 497661, 0, 783969, 0, 1189311, 0, 1747059, 0, 2497109, 0, 3484867, 0, 4763439, 0, 6392095, 0, 8439027, 0, 10979255, 0, 14097919, 0, 17887629, 0, 22452391, 0]

cp's OEIS Frontend

A225347 Number of 7Xn -1,1 arrays such that the sum over i=1..7,j=1..n of i*x(i,j) is zero, the sum of x(i,j) is zero, and rows are nondecreasing (number of ways to distribute n-across galley oarsmen left-right at 7 fore-aft positions so that there are no turning moments on the ship).

Table of values

List of values