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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”).

A057497 as a simple table

na(n)
11
21
31
42
56
617
713
817
930
1060
11555
12990
131616
142168
152467
162648
172294
181892
191283
20810

[1,1,1,2,6,17,13,17,30,60,555,990,1616,2168,2467,
 2648,2294,1892,1283,810]