The OEIS mourns the passing of
Jim Simons
and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
login
The OEIS is supported by
the many generous donors to the OEIS Foundation
.
Hints
(Greetings from
The On-Line Encyclopedia of Integer Sequences
!)
A180981
as a triangular array
1
1
1
0
1
1
0
1
2
1
0
0
1
2
1
0
0
1
2
3
1
0
0
0
1
3
3
1
0
0
0
1
3
5
4
1
0
0
0
0
1
5
6
4
1
0
0
0
0
1
3
8
8
5
1
0
0
0
0
0
1
6
12
10
5
1
0
0
0
0
0
1
4
12
18
13
6
1
0
0
0
0
0
0
1
8
20
24
15
6
1
0
0
0
0
0
0
1
4
18
32
33
A180981
as a square array
1
1
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
0
0
0
0
0
0
0
0
0
0
1
2
1
1
0
0
0
0
0
0
0
0
1
2
2
1
1
0
0
0
0
0
0
1
3
3
3
1
1
0
0
0
0
1
3
5
5
3
1
1
0
0
1
4
6
8
6
4
1
1
1
4
8
12
12
8
4
1
5
10
18
20
18
1
5
13
24
32
1
6
15
33
1
6
1
A180981
as an upper right triangle
1
1
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
0
0
0
0
0
0
0
0
0
0
1
2
1
1
0
0
0
0
0
0
0
0
1
2
2
1
1
0
0
0
0
0
0
1
3
3
3
1
1
0
0
0
0
1
3
5
5
3
1
1
0
0
1
4
6
8
6
4
1
1
1
4
8
12
12
8
4
1
5
10
18
20
18
1
5
13
24
32
1
6
15
33
1
6
1
Lookup
|
Welcome
|
Wiki
|
Register
|
Music
|
Plot 2
|
Demos
|
Index
|
Browse
|
More
|
WebCam
Contribute new seq. or comment
|
Format
|
Style Sheet
|
Transforms
|
Superseeker
|
Recents
The OEIS Community
| Maintained by
The OEIS Foundation Inc.
License Agreements, Terms of Use, Privacy Policy.
.
Last modified May 23 06:30 EDT 2024. Contains 372760 sequences. (Running on oeis4.)
