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A275421 as a triangular array

1
11
311
5411
128411
30239411
7957269411
22716068279411
71045619771279411
2322140256720872279411
80714468174860421172279411
295031507155551874

A275421 as a square array

11351230792277102322807129503
114823571604561402446815071
1149266819756717485555
114927712086041874
11492772211
11492772
114927
1149
114
11
1
11351230792277102322807129503
114823571604561402446815071
1149266819756717485555
114927712086041874
11492772211
11492772
114927
1149
114
11
1