A049139 - OEIS

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A049139 as a simple table

`n`		`a(n)`
`1`		`1`
`2`		`1`
`3`		`2`
`4`		`6`
`5`		`20`
`6`		`72`
`7`		`272`
`8`		`1063`
`9`		`4262`
`10`		`17432`
`11`		`72448`
`12`		`305074`
`13`		`1298812`
`14`		`5581188`
`15`		`24175560`
`16`		`105448157`
`17`		`462745106`
`18`		`2041634108`
`19`		`9050879192`
`20`		`40296196096`
`21`		`180099939464`
`22`		`807757872276`
`23`		`3634378951656`
`24`		`16399912908504`
`25`		`74201196229816`

[1,1,2,6,20,72,272,1063,4262,17432,72448,305074, 1298812,5581188,24175560,105448157,462745106, 2041634108,9050879192,40296196096,180099939464, 807757872276,3634378951656,16399912908504, 74201196229816]

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Last modified April 19 19:02 EDT 2024. Contains 371798 sequences. (Running on oeis4.)