A103715 - cp's OEIS frontend

A103715 Define a(1)=0, a(2)=0, a(3)=1, a(4)=3, a(5)=18, a(6)=22, a(7)=119, a(8)=285. Then a(n) = a(n-8) + 4sqrt(420a(n-4)^2 + 420*a(n-4) + 1).

n	a(n)
1	0
2	0
3	1
4	3
5	18
6	22
7	119
8	285
9	1516
10	1844
11	9797
12	23407
13	124334
14	151226
15	803275
16	1919129
17	10193912
18	12398728
19	65858793
20	157345211
21	835776490
22	1016544510
23	5399617791
24	12900388213
25	68523478308
26	83344251132
27	442702800109

[0, 0, 1, 3, 18, 22, 119, 285, 1516, 1844, 9797, 23407, 124334, 151226, 803275, 1919129, 10193912, 12398728, 65858793, 157345211, 835776490, 1016544510, 5399617791, 12900388213, 68523478308, 83344251132, 442702800109]

cp's OEIS Frontend

A103715 Define a(1)=0, a(2)=0, a(3)=1, a(4)=3, a(5)=18, a(6)=22, a(7)=119, a(8)=285. Then a(n) = a(n-8) + 4sqrt(420a(n-4)^2 + 420*a(n-4) + 1).

Table of values

List of values

cp's OEIS Frontend

A103715 Define a(1)=0, a(2)=0, a(3)=1, a(4)=3, a(5)=18, a(6)=22, a(7)=119, a(8)=285. Then a(n) = a(n-8) + 4*sqrt(420*a(n-4)^2 + 420*a(n-4) + 1).

Table of values

List of values

A103715 Define a(1)=0, a(2)=0, a(3)=1, a(4)=3, a(5)=18, a(6)=22, a(7)=119, a(8)=285. Then a(n) = a(n-8) + 4sqrt(420a(n-4)^2 + 420*a(n-4) + 1).