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A121721 as a triangular array

1
02
-1225
-9125117
-36-724117356
-100-3416116356850
-225-98-111083558501737
-441-223-758134784917373185
-784-439-20017320841173631855392
-1296-782-416-1082568141728318453928586
-2025-1294-759-324131750

A121721 as a square array

10-1-9-36-100-225-441-784-1296-2025
221-7-34-98-223-439-782-1294
25252416-11-75-200-416-759
1171171161088117-108-324
356356355347320256131
850850849841814750
1737173717361728
318531853184
53925392
8586
10-1-9-36-100-225-441-784-1296-2025
221-7-34-98-223-439-782-1294
25252416-11-75-200-416-759
1171171161088117-108-324
356356355347320256131
850850849841814750
1737173717361728
318531853184
53925392
8586