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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”).

A146825 as a simple table

na(n)
11
21
31
41
51
61
71
81
99
109
1133
1233
1381
1481
15501
16501
179765
189765
19253829
20253829
215201161
225201161

[1,1,1,1,1,1,1,1,9,9,33,33,81,81,501,501,9765,
 9765,253829,253829,5201161,5201161]