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A289501 as a simple table

na(n)
01
11
22
34
412
532
6112
7352
81296
94448
1016640
1159968
12231168
13856960
143334400
1512679424
1649991424
17192890880
18767229952
192998427648
2012015527936
2147438950400
22191117033472
23760625733632
243082675150848
2512346305839104
2650223511928832
27202359539335168

[1,1,2,4,12,32,112,352,1296,4448,16640,59968,
 231168,856960,3334400,12679424,49991424,192890880,
 767229952,2998427648,12015527936,47438950400,
 191117033472,760625733632,3082675150848,
 12346305839104,50223511928832,202359539335168]