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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”).

A247661 as a simple table

na(n)
01
11
23
36
412
520
635
756
892
9142
10221
11330
12496
13724
141056
151512
162155
173028
184240
195866
208085

[1,1,3,6,12,20,35,56,92,142,221,330,496,724,1056,
 1512,2155,3028,4240,5866,8085]