A221988 - OEIS

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A221988 as a simple table

`n`		`a(n)`
`0`		`1`
`1`		`2`
`2`		`6`
`3`		`24`
`4`		`116`
`5`		`664`
`6`		`4392`
`7`		`32928`
`8`		`276016`
`9`		`2557856`
`10`		`25965408`
`11`		`286538112`
`12`		`3415359296`
`13`		`43727878528`
`14`		`598510015104`
`15`		`8720853182976`
`16`		`134778021389056`
`17`		`2202055694727680`
`18`		`37923940767905280`
`19`		`686639853639505920`
`20`		`13038833241899856896`
`21`		`259119925532534413312`

[1,2,6,24,116,664,4392,32928,276016,2557856, 25965408,286538112,3415359296,43727878528, 598510015104,8720853182976,134778021389056, 2202055694727680,37923940767905280, 686639853639505920,13038833241899856896, 259119925532534413312]

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Last modified April 25 13:02 EDT 2024. Contains 371969 sequences. (Running on oeis4.)