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A000253 as a simple table

na(n)
00
11
24
311
427
563
6142
7312
8673
91432
103015
116295
1213055
1326926
1455284
15113081
16230572
17468883
18951347
191926527
203894878
217863152
2215855105
2331936240
2464269135
25129234351
26259690239
27521524126
281046810092
292100221753
304212028452
318444387067

[0,1,4,11,27,63,142,312,673,1432,3015,6295,13055,
 26926,55284,113081,230572,468883,951347,1926527,
 3894878,7863152,15855105,31936240,64269135,
 129234351,259690239,521524126,1046810092,
 2100221753,4212028452,8444387067]