login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A127172 as a triangular array

1
31
301
6301
30001
933001
3000001
106030001
603000001
9300030000
1

A127172 as a square array

133639310691
103030603
10030030
1000300
100000
10003
1000
100
10
0
133639310691
103030603
10030030
1000300
100000
10003
1000
100
10
0