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A212221 as a triangular array

0
00
001
0013
001126
001307810
0016647434015
00113822384780109521
00128295464642032955285628
00157038958385660617775168546641236

A212221 as a square array

0000000000
000000000
11111111
3123066138282570
6784742238954638958
10340478046420385660
15109532955617775
212856168546
286412
36
0000000000
000000000
11111111
3123066138282570
6784742238954638958
10340478046420385660
15109532955617775
212856168546
286412
36