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A050227 as a triangular array

1
31
731
15831
3119831
634320831
127944720831
2552011074820831
5114232381114820831
10238805202511124820831
2047181511215582551124820831
40953719

A050227 as a square array

137153163127255511102320474095
13819439420142388018153719
13820471072385201121
1382048111251558
1382048112255
1382048112
1382048
13820
138
13
1
137153163127255511102320474095
13819439420142388018153719
13820471072385201121
1382048111251558
1382048112255
1382048112
1382048
13820
138
13
1