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A257501 as a triangular array

1
41
1481
4844121
16520890161
572910544152201
2002380829071120230241
7072155041436470842000324281
25194620166729840480146253248434321
90440245157303600

A257501 as a square array

141448165572200270722519490440
184420891038081550462016245157
1129054429071436467298303600
1161521120708440480
120230200014625
1243243248
128434
132
1
141448165572200270722519490440
184420891038081550462016245157
1129054429071436467298303600
1161521120708440480
120230200014625
1243243248
128434
132
1