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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”).

A207667 as a simple table

na(n)
11
22
34
46
510
630
770
8510
92590
10131070
113359230
12167247870
138589934590
1413985925344264190

[1,2,4,6,10,30,70,510,2590,131070,3359230,
 167247870,8589934590,13985925344264190]