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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”).

A220877 as a simple table

na(n)
11
25
345
4485
55485
662405
7702445
87770085
984292525
10897101125
119379187885
1296487985125
13978249364205
149787794765765
1596752629782125
16945738292868325

[1,5,45,485,5485,62405,702445,7770085,84292525,
 897101125,9379187885,96487985125,978249364205,
 9787794765765,96752629782125,945738292868325]