A066770 - cp's OEIS frontend

A066770 a(n) = 5^nsin(2narctan(1/2)) or numerator of tan(2n*arctan(1/2)).

n	a(n)
1	4
2	24
3	44
4	-336
5	-3116
6	-10296
7	16124
8	354144
9	1721764
10	1476984
11	-34182196
12	-242017776
13	-597551756
14	2465133864
15	29729597084
16	116749235904
17	-42744511676
18	-3175197967656
19	-17982575014036
20	-28515500892816
21	278471369994004
22	2383715742284424
23	7340510203856444

[4, 24, 44, -336, -3116, -10296, 16124, 354144, 1721764, 1476984, -34182196, -242017776, -597551756, 2465133864, 29729597084, 116749235904, -42744511676, -3175197967656, -17982575014036, -28515500892816, 278471369994004, 2383715742284424, 7340510203856444]

cp's OEIS Frontend

A066770 a(n) = 5^nsin(2narctan(1/2)) or numerator of tan(2n*arctan(1/2)).

Table of values

List of values

cp's OEIS Frontend

A066770 a(n) = 5^n*sin(2n*arctan(1/2)) or numerator of tan(2n*arctan(1/2)).

Table of values

List of values

A066770 a(n) = 5^nsin(2narctan(1/2)) or numerator of tan(2n*arctan(1/2)).