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A209666 as a triangular array

1
27
31855
550216631
711872927808001
1130126211295445865130453
156848535551962418708205542323483
22162128689241634130705552802041735302848916087
3036209174910121966783210327110221249916854017097201129559068

A209666 as a square array

1235711152230
7185011830168416213620
55216729262185352868991749
631278012954551962416341012196
80014586524187013070556783210
130453820554528020432711022
232348317353028124991685
48916087401709720
1129559068
1235711152230
7185011830168416213620
55216729262185352868991749
631278012954551962416341012196
80014586524187013070556783210
130453820554528020432711022
232348317353028124991685
48916087401709720
1129559068