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A001856 as a simple table

na(n)
11
22
34
48
516
621
742
851
9102
10112
11224
12235
13470
14486
15972
16990
171980
182002
194004
204027
218054
228078
2316156
2416181
2532362
2632389
2764778
2864806
29129612
30129641
31259282
32259313
33518626
34518658
351037316
361037349
372074698
382074734
394149468

[1,2,4,8,16,21,42,51,102,112,224,235,470,486,972,
 990,1980,2002,4004,4027,8054,8078,16156,16181,
 32362,32389,64778,64806,129612,129641,259282,
 259313,518626,518658,1037316,1037349,2074698,
 2074734,4149468]