A027121 - OEIS

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A027121 as a simple table

`n`		`a(n)`
`2`		`1`
`3`		`4`
`4`		`13`
`5`		`40`
`6`		`120`
`7`		`352`
`8`		`1022`
`9`		`2948`
`10`		`8473`
`11`		`24304`
`12`		`69649`
`13`		`199544`
`14`		`571795`
`15`		`1639244`
`16`		`4702499`
`17`		`13500396`
`18`		`38790727`
`19`		`111555296`
`20`		`321100627`
`21`		`925086012`
`22`		`2667533646`
`23`		`7698716068`
`24`		`22238169212`
`25`		`64289860528`
`26`		`186010834243`
`27`		`538611262492`

[1,4,13,40,120,352,1022,2948,8473,24304,69649, 199544,571795,1639244,4702499,13500396,38790727, 111555296,321100627,925086012,2667533646, 7698716068,22238169212,64289860528,186010834243, 538611262492]

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Last modified May 20 10:58 EDT 2024. Contains 372712 sequences. (Running on oeis4.)