login

A132728 as a triangular array

1
17
171
1717
17171
171717
1717171
17171717
171717171
1717171717
17171717171

A132728 as a square array

11111111111
7777777777
111111111
77777777
1111111
777777
11111
7777
111
77
1
11111111111
7777777777
111111111
77777777
1111111
777777
11111
7777
111
77
1