A055793 - cp's OEIS frontend

A055793 Numbers k such that k and floor[k/3] are both squares; i.e., squares which remain squares when written in base 3 and last digit is removed.

n	a(n)
1	0
2	1
3	4
4	49
5	676
6	9409
7	131044
8	1825201
9	25421764
10	354079489
11	4931691076
12	68689595569
13	956722646884
14	13325427460801
15	185599261804324
16	2585064237799729
17	36005300067391876
18	501489136705686529
19	6984842613812219524
20	97286307456665386801
21	1355023461779503195684
22	18873042157456379352769

[0, 1, 4, 49, 676, 9409, 131044, 1825201, 25421764, 354079489, 4931691076, 68689595569, 956722646884, 13325427460801, 185599261804324, 2585064237799729, 36005300067391876, 501489136705686529, 6984842613812219524, 97286307456665386801, 1355023461779503195684, 18873042157456379352769]

cp's OEIS Frontend

A055793 Numbers k such that k and floor[k/3] are both squares; i.e., squares which remain squares when written in base 3 and last digit is removed.

Table of values

List of values