A000390 - OEIS

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A000390 as a simple table

`n`		`a(n)`
`1`		`1`
`2`		`6`
`3`		`21`
`4`		`71`
`5`		`216`
`6`		`657`
`7`		`1907`
`8`		`5507`
`9`		`15522`
`10`		`43352`
`11`		`119140`
`12`		`323946`
`13`		`869476`
`14`		`2308071`
`15`		`6056581`
`16`		`15724170`
`17`		`40393693`
`18`		`102736274`
`19`		`258790004`
`20`		`645968054`
`21`		`1598460229`
`22`		`3923114261`
`23`		`9554122089`
`24`		`23098084695`
`25`		`55458417125`
`26`		`132293945737`
`27`		`313657570114`

[1,6,21,71,216,657,1907,5507,15522,43352,119140, 323946,869476,2308071,6056581,15724170,40393693, 102736274,258790004,645968054,1598460229, 3923114261,9554122089,23098084695,55458417125, 132293945737,313657570114]

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Last modified April 18 22:18 EDT 2024. Contains 371782 sequences. (Running on oeis4.)