login

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”).

A147074 as a simple table

na(n)
11
21
31
41
55
69
725
839
9151
10463
112967
1212351
13101811
14497317
155967627
1641101207
17709472803

[1,1,1,1,5,9,25,39,151,463,2967,12351,101811,
 497317,5967627,41101207,709472803]