A018907 - OEIS

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A018907 as a simple table

`n`		`a(n)`
`0`		`2`
`1`		`7`
`2`		`25`
`3`		`90`
`4`		`325`
`5`		`1174`
`6`		`4241`
`7`		`15321`
`8`		`55349`
`9`		`199956`
`10`		`722370`
`11`		`2609667`
`12`		`9427803`
`13`		`34059315`
`14`		`123044249`
`15`		`444515318`
`16`		`1605876501`
`17`		`5801463374`
`18`		`20958633656`
`19`		`75716124779`
`20`		`273535557978`
`21`		`988187148996`
`22`		`3569970385786`
`23`		`12897039359739`
`24`		`46592438107869`
`25`		`168321986797406`

[2,7,25,90,325,1174,4241,15321,55349,199956, 722370,2609667,9427803,34059315,123044249, 444515318,1605876501,5801463374,20958633656, 75716124779,273535557978,988187148996, 3569970385786,12897039359739,46592438107869, 168321986797406]

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Last modified April 19 21:09 EDT 2024. Contains 371798 sequences. (Running on oeis4.)