A272482 - cp's OEIS frontend

A272482 a(n) equals the coefficient of x^(2n)y^n/(2n)! in cos((x - xy)/2) / cos((x + x*y)/2).

n	a(n)
0	1
1	1
2	3
3	25
4	455
5	14301
6	683067
7	45956625
8	4136759055
9	479777869285
10	69653708853443
11	12371662732650585
12	2638795469278520279
13	665531624367489426925
14	195911141957772574473675
15	66564029296445548535841825
16	25853886516555100370014075935
17	11383146182215029605579802759285
18	5639331535011059552351840518792275
19	3122923020612123544335165657648107625
20	1921790647828858936591348065677192750055

[1, 1, 3, 25, 455, 14301, 683067, 45956625, 4136759055, 479777869285, 69653708853443, 12371662732650585, 2638795469278520279, 665531624367489426925, 195911141957772574473675, 66564029296445548535841825, 25853886516555100370014075935, 11383146182215029605579802759285, 5639331535011059552351840518792275, 3122923020612123544335165657648107625, 1921790647828858936591348065677192750055]

cp's OEIS Frontend

A272482 a(n) equals the coefficient of x^(2n)y^n/(2n)! in cos((x - xy)/2) / cos((x + x*y)/2).

Table of values

List of values

cp's OEIS Frontend

A272482 a(n) equals the coefficient of x^(2*n)*y^n/(2*n)! in cos((x - x*y)/2) / cos((x + x*y)/2).

Table of values

List of values

A272482 a(n) equals the coefficient of x^(2n)y^n/(2n)! in cos((x - xy)/2) / cos((x + x*y)/2).