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A221918 as a triangular array

1
21
363
44122
51015205
63212303
714212835427
882484024564
918936451863729
105302010157040905
11223344556677889911011
1212123604842436601326

A221918 as a square array

123456789101112
1641031481852212
31215221249303312
220122883620443
530354045105560
342241815664
75663707784
472408824
9909936
511060
11132
6
123456789101112
1641031481852212
31215221249303312
220122883620443
530354045105560
342241815664
75663707784
472408824
9909936
511060
11132
6