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Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A001180 as a simple table

na(n)
11
21
32
43
53
65
79
816
928
1050
1189
12159
13285
14510
15914
161639
172938
185269
199451
2016952

[1,1,2,3,3,5,9,16,28,50,89,159,285,510,914,1639,
 2938,5269,9451,16952]