A027991 - OEIS

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A027991 as a simple table

`n`		`a(n)`
`1`		`1`
`2`		`3`
`3`		`12`
`4`		`40`
`5`		`130`
`6`		`404`
`7`		`1227`
`8`		`3653`
`9`		`10720`
`10`		`31090`
`11`		`89316`
`12`		`254568`
`13`		`720757`
`14`		`2029095`
`15`		`5684340`
`16`		`15855964`
`17`		`44061862`
`18`		`122032508`
`19`		`336966015`
`20`		`927953705`
`21`		`2549229256`
`22`		`6987648358`
`23`		`19115124552`
`24`		`52194037200`
`25`		`142274514025`
`26`		`387215773899`

[1,3,12,40,130,404,1227,3653,10720,31090,89316, 254568,720757,2029095,5684340,15855964,44061862, 122032508,336966015,927953705,2549229256, 6987648358,19115124552,52194037200,142274514025, 387215773899]

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Last modified May 5 00:40 EDT 2024. Contains 372257 sequences. (Running on oeis4.)