A257661 - cp's OEIS frontend

A257661 Number of n X n upper triangular matrices (m_{i,j}) of nonnegative integers with (Sum_{j=h..n} m_{h,j} - Sum_{i=1..h-1} m_{i,h}) in {-1,+1} for all h in {1,...,n}.

n	a(n)
0	1
1	1
2	3
3	13
4	91
5	957
6	14883
7	335685
8	10809115
9	489983429
10	30878036187
11	2674610665285
12	315157973368499
13	50044685318592821
14	10616892819871806779
15	2985356872553448786917
16	1104511676749585428665683
17	534037023412133157982099237
18	335321015907953576212969151451

[1, 1, 3, 13, 91, 957, 14883, 335685, 10809115, 489983429, 30878036187, 2674610665285, 315157973368499, 50044685318592821, 10616892819871806779, 2985356872553448786917, 1104511676749585428665683, 534037023412133157982099237, 335321015907953576212969151451]

cp's OEIS Frontend

A257661 Number of n X n upper triangular matrices (m_{i,j}) of nonnegative integers with (Sum_{j=h..n} m_{h,j} - Sum_{i=1..h-1} m_{i,h}) in {-1,+1} for all h in {1,...,n}.

Table of values

List of values