A081880 - cp's OEIS frontend

A081880 Triangle read by rows: n-th row gives trajectory of 2n under the map x->(x^2-4)/6, stopping when the next term would be negative or nonintegral.

n	a(n)
0	0
1	2
2	0
3	4
4	2
5	0
6	6
7	8
8	10
9	16
10	42
11	10
12	16
13	42
14	12
15	14
16	32
17	170
18	4816
19	3865642
20	2490531345360
21	16
22	42
23	18
24	20
25	66
26	22
27	80
28	1066
29	189392
30	5978221610
31	5956522269711832016
32	5913359591595499145281505571167104042
33	5827970276585748074286667660065476529979312208145367609757859954142122960
34	24
35	26

[0, 2, 0, 4, 2, 0, 6, 8, 10, 16, 42, 10, 16, 42, 12, 14, 32, 170, 4816, 3865642, 2490531345360, 16, 42, 18, 20, 66, 22, 80, 1066, 189392, 5978221610, 5956522269711832016, 5913359591595499145281505571167104042, 5827970276585748074286667660065476529979312208145367609757859954142122960, 24, 26]

cp's OEIS Frontend

A081880 Triangle read by rows: n-th row gives trajectory of 2n under the map x->(x^2-4)/6, stopping when the next term would be negative or nonintegral.

Table of values

List of values