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”).

A008278 as a triangular array

1
11
131
1671
11025151
1156590311
121140350301631
128266105017019661271
13646226466951777030252551
145750588022827425253410593305111

A008278 as a square array

1111111111
136101521283645
172565140266462750
11590350105026465880
1313011701695122827
163966777042525
1127302534105
12559330
1511
1
1111111111
136101521283645
172565140266462750
11590350105026465880
1313011701695122827
163966777042525
1127302534105
12559330
1511
1