A009721 - OEIS

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A009721 as a simple table

`n`		`a(n)`
`0`		`0`
`1`		`1`
`2`		`2`
`3`		`3`
`4`		`20`
`5`		`157`
`6`		`902`
`7`		`6895`
`8`		`77352`
`9`		`837145`
`10`		`9239882`
`11`		`124480059`
`12`		`1864519868`
`13`		`28461793141`
`14`		`470175087566`
`15`		`8596601614567`
`16`		`165789417707088`
`17`		`3347308657310641`
`18`		`72262366126097810`
`19`		`1655981959056540147`
`20`		`39676337445225379172`
`21`		`996780437366905850317`

[0,1,2,3,20,157,902,6895,77352,837145,9239882, 124480059,1864519868,28461793141,470175087566, 8596601614567,165789417707088,3347308657310641, 72262366126097810,1655981959056540147, 39676337445225379172,996780437366905850317]

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Last modified April 23 06:04 EDT 2024. Contains 371906 sequences. (Running on oeis4.)