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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”).

A121972 as a simple table

na(n)
11
214
3216
42442
524611
6223717
71894520
815169211
9116213717
108588186640

[1,14,216,2442,24611,223717,1894520,15169211,
 116213717,8588186640]