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A045690 as a simple table

na(n)
11
21
32
43
56
610
720
837
974
10142
11284
12558
131116
142212
154424
168811
1717622
1835170
1970340
20140538
21281076
22561868
231123736
242246914
254493828
268986540
2717973080
2835943948
2971887896
30143771368
31287542736
32575076661
331150153322
342300289022
354600578044
369201120918

[1,1,2,3,6,10,20,37,74,142,284,558,1116,2212,4424,
 8811,17622,35170,70340,140538,281076,561868,
 1123736,2246914,4493828,8986540,17973080,35943948,
 71887896,143771368,287542736,575076661,1150153322,
 2300289022,4600578044,9201120918]