A007021 - OEIS

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A007021 as a simple table

`n`		`a(n)`
`3`		`1`
`4`		`1`
`5`		`1`
`6`		`1`
`7`		`1`
`8`		`2`
`9`		`4`
`10`		`10`
`11`		`25`
`12`		`87`
`13`		`313`
`14`		`1357`
`15`		`6244`
`16`		`30926`
`17`		`158428`
`18`		`836749`
`19`		`4504607`
`20`		`24649284`
`21`		`136610879`
`22`		`765598927`
`23`		`4332047595`
`24`		`24724362117`
`25`		`142205424580`
`26`		`823687567019`
`27`		`4801749063379`

[1,1,1,1,1,2,4,10,25,87,313,1357,6244,30926, 158428,836749,4504607,24649284,136610879, 765598927,4332047595,24724362117,142205424580, 823687567019,4801749063379]

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Last modified September 13 22:05 EDT 2024. Contains 375910 sequences. (Running on oeis4.)