A331505 - OEIS

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A331505 as a simple table

`n`		`a(n)`
`1`		`1`
`2`		`1`
`3`		`3`
`4`		`15`
`5`		`45`
`6`		`455`
`7`		`1330`
`8`		`20475`
`9`		`58905`
`10`		`1221759`
`11`		`3478761`
`12`		`90858768`
`13`		`256851595`
`14`		`8093990190`
`15`		`22760723700`
`16`		`840261910995`
`17`		`2353351951665`
`18`		`99615373765775`
`19`		`278110855548955`
`20`		`13278694407181203`
`21`		`36976937738226486`

[1,1,3,15,45,455,1330,20475,58905,1221759,3478761, 90858768,256851595,8093990190,22760723700, 840261910995,2353351951665,99615373765775, 278110855548955,13278694407181203, 36976937738226486]

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Last modified August 9 05:09 EDT 2024. Contains 375027 sequences. (Running on oeis4.)