A073410 - cp's OEIS frontend

A073410 Number of permutations p of (1,2,3,...,n) such that 1(-1)^p(1)+2(-1)^p(2)+3(-1)^p(3)+...+n(-1)^p(n)=0.

n	a(n)
0	1
1	0
2	0
3	2
4	8
5	0
6	0
7	576
8	4608
9	0
10	0
11	2505600
12	30067200
13	0
14	0
15	53444966400
16	855119462400
17	0
18	0
19	3587014803456000
20	71740296069120000
21	0
22	0
23	584198928937451520000
24	14020774294498836480000
25	0
26	0
27	196340349691596912721920000
28	5497529791364713556213760000
29	0
30	0

[1, 0, 0, 2, 8, 0, 0, 576, 4608, 0, 0, 2505600, 30067200, 0, 0, 53444966400, 855119462400, 0, 0, 3587014803456000, 71740296069120000, 0, 0, 584198928937451520000, 14020774294498836480000, 0, 0, 196340349691596912721920000, 5497529791364713556213760000, 0, 0]

cp's OEIS Frontend

A073410 Number of permutations p of (1,2,3,...,n) such that 1(-1)^p(1)+2(-1)^p(2)+3(-1)^p(3)+...+n(-1)^p(n)=0.

Table of values

List of values

cp's OEIS Frontend

A073410 Number of permutations p of (1,2,3,...,n) such that 1*(-1)^p(1)+2*(-1)^p(2)+3*(-1)^p(3)+...+n*(-1)^p(n)=0.

Table of values

List of values

A073410 Number of permutations p of (1,2,3,...,n) such that 1(-1)^p(1)+2(-1)^p(2)+3(-1)^p(3)+...+n(-1)^p(n)=0.