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A000257 as a simple table

na(n)
01
11
23
312
456
5288
61584
79152
854912
9339456
102149888
1113891584
1291287552
13608583680
144107939840
1528030648320
16193100021760
171341536993280
189390758952960
1966182491668480
20469294031831040
213346270487838720
2223981605162844160
23172667557172477952

[1,1,3,12,56,288,1584,9152,54912,339456,2149888,
 13891584,91287552,608583680,4107939840,
 28030648320,193100021760,1341536993280,
 9390758952960,66182491668480,469294031831040,
 3346270487838720,23981605162844160,
 172667557172477952]