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A221200 as a triangular array

0
10
290
410490
8196462890
16720902521216810
3264005870042771697698010
643427225185694984812202770094492571210
128242064320853761026177156433687328961434049206723329290
256

A221200 as a square array

01248163264128256
0910196720640034272242064
04946902558700251856932085376
028921242771649848121026177156
0168197620277009433687328
098014492961434049
05712120672
0332929
0
01248163264128256
0910196720640034272242064
04946902558700251856932085376
028921242771649848121026177156
0168197620277009433687328
098014492961434049
05712120672
0332929
0