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A157640 as a simple table

na(n)
01
11
21
31
48
51
61
739
839
91
101
11160
12780
13160
141
151
16605
1712100
1812100
19605
201
211
222184
23165165
24677600
25165165
262184
271
281
297651
302088723
3132401985
3232401985
332088723
347651
351
361
3726240
3825095280
391405335680
405313925540
411405335680
4225095280

[1,1,1,1,8,1,1,39,39,1,1,160,780,160,1,1,605,
 12100,12100,605,1,1,2184,165165,677600,165165,
 2184,1,1,7651,2088723,32401985,32401985,2088723,
 7651,1,1,26240,25095280,1405335680,5313925540,
 1405335680,25095280]