A133111 - cp's OEIS frontend

A133111 a(n) = (1/(1!2!3!4!))Sum_{1 <= x_1, x_2, x_3, x_4 <= n} |det V(x_1,x_2,x_3,x_4)|, where V(x_1,x_2,x_3,x_4) is the Vandermonde matrix of order 4.

n	a(n)
1	0
2	0
3	0
4	1
5	16
6	126
7	672
8	2772
9	9504
10	28314
11	75504
12	184041
13	416416
14	884884
15	1782144
16	3426384
17	6325632
18	11267532
19	19442016
20	32605881
21	53300016
22	85131970
23	133138720
24	204246900
25	307850400
26	456528150
27	666928080
28	960846705
29	1366537536
30	1920285576
31	2668289536

[0, 0, 0, 1, 16, 126, 672, 2772, 9504, 28314, 75504, 184041, 416416, 884884, 1782144, 3426384, 6325632, 11267532, 19442016, 32605881, 53300016, 85131970, 133138720, 204246900, 307850400, 456528150, 666928080, 960846705, 1366537536, 1920285576, 2668289536]

cp's OEIS Frontend

A133111 a(n) = (1/(1!2!3!4!))Sum_{1 <= x_1, x_2, x_3, x_4 <= n} |det V(x_1,x_2,x_3,x_4)|, where V(x_1,x_2,x_3,x_4) is the Vandermonde matrix of order 4.

Table of values

List of values

cp's OEIS Frontend

A133111 a(n) = (1/(1!*2!*3!*4!))*Sum_{1 <= x_1, x_2, x_3, x_4 <= n} |det V(x_1,x_2,x_3,x_4)|, where V(x_1,x_2,x_3,x_4) is the Vandermonde matrix of order 4.

Table of values

List of values

A133111 a(n) = (1/(1!2!3!4!))Sum_{1 <= x_1, x_2, x_3, x_4 <= n} |det V(x_1,x_2,x_3,x_4)|, where V(x_1,x_2,x_3,x_4) is the Vandermonde matrix of order 4.