A065180 - OEIS

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A065180 as a simple table

`n`		`a(n)`
`1`		`1`
`2`		`4`
`3`		`20`
`4`		`90`
`5`		`420`
`6`		`1910`
`7`		`8820`
`8`		`40590`
`9`		`187880`
`10`		`871494`
`11`		`4057620`
`12`		`18945960`
`13`		`88738020`
`14`		`416787030`
`15`		`1962922276`
`16`		`9268287390`
`17`		`43868210820`
`18`		`208109782580`
`19`		`989400443220`
`20`		`4713395564772`
`21`		`22497100553820`
`22`		`107572434560790`
`23`		`515241748300020`

[1,4,20,90,420,1910,8820,40590,187880,871494, 4057620,18945960,88738020,416787030,1962922276, 9268287390,43868210820,208109782580,989400443220, 4713395564772,22497100553820,107572434560790, 515241748300020]

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Last modified June 6 19:21 EDT 2024. Contains 373134 sequences. (Running on oeis4.)