A005558 - OEIS

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A005558 as a simple table

`n`		`a(n)`
`0`		`1`
`1`		`1`
`2`		`3`
`3`		`6`
`4`		`20`
`5`		`50`
`6`		`175`
`7`		`490`
`8`		`1764`
`9`		`5292`
`10`		`19404`
`11`		`60984`
`12`		`226512`
`13`		`736164`
`14`		`2760615`
`15`		`9202050`
`16`		`34763300`
`17`		`118195220`
`18`		`449141836`
`19`		`1551580888`
`20`		`5924217936`
`21`		`20734762776`
`22`		`79483257308`
`23`		`281248448936`
`24`		`1081724803600`
`25`		`3863302870000`
`26`		`14901311070000`
`27`		`53644719852000`

[1,1,3,6,20,50,175,490,1764,5292,19404,60984, 226512,736164,2760615,9202050,34763300,118195220, 449141836,1551580888,5924217936,20734762776, 79483257308,281248448936,1081724803600, 3863302870000,14901311070000,53644719852000]

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Last modified April 17 23:23 EDT 2024. Contains 371767 sequences. (Running on oeis4.)