A127689 - cp's OEIS frontend

A127689 a(1)=3; for n>1, a(n) is least number such that a(n) > a(n-1) and a(1)^2+...+a(n)^2 is a square.

n	a(n)
1	3
2	4
3	12
4	84
5	132
6	12324
7	15960
8	26280
9	27300
10	66660
11	115188
12	9777193284
13	23465263884
14	48701491080
15	40900397690640
16	680008604512020
17	127049882801497788
18	247290967245178188
19	335580091290976716
20	1045885075937364972
21	1607091702050097396
22	3419793695168900508
23	5138020847719969956
24	10059508412964112740

[3, 4, 12, 84, 132, 12324, 15960, 26280, 27300, 66660, 115188, 9777193284, 23465263884, 48701491080, 40900397690640, 680008604512020, 127049882801497788, 247290967245178188, 335580091290976716, 1045885075937364972, 1607091702050097396, 3419793695168900508, 5138020847719969956, 10059508412964112740]

cp's OEIS Frontend

A127689 a(1)=3; for n>1, a(n) is least number such that a(n) > a(n-1) and a(1)^2+...+a(n)^2 is a square.

Table of values

List of values