A000421 - OEIS

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A000421 as a simple table

`n`		`a(n)`
`1`		`1`
`2`		`2`
`3`		`6`
`4`		`20`
`5`		`91`
`6`		`509`
`7`		`3608`
`8`		`31856`
`9`		`340416`
`10`		`4269971`
`11`		`61133757`
`12`		`978098997`
`13`		`17228295555`
`14`		`330552900516`
`15`		`6853905618223`
`16`		`152626436936272`
`17`		`3631575281503404`
`18`		`91928898608055819`
`19`		`2466448432564961852`
`20`		`69907637101781318907`

[1,2,6,20,91,509,3608,31856,340416,4269971, 61133757,978098997,17228295555,330552900516, 6853905618223,152626436936272,3631575281503404, 91928898608055819,2466448432564961852, 69907637101781318907]

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Last modified April 24 20:06 EDT 2024. Contains 371963 sequences. (Running on oeis4.)