A020087 - OEIS

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A020087 as a simple table

`n`		`a(n)`
`0`		`1`
`1`		`0`
`2`		`0`
`3`		`0`
`4`		`2`
`5`		`9`
`6`		`50`
`7`		`318`
`8`		`2310`
`9`		`19060`
`10`		`176310`
`11`		`1807181`
`12`		`20330788`
`13`		`249052161`
`14`		`3299941145`
`15`		`47024161317`
`16`		`717118460090`
`17`		`11653174976468`
`18`		`201017268344078`
`19`		`3668565147279423`
`20`		`70619879085128903`
`21`		`1430052551473860292`

[1,0,0,0,2,9,50,318,2310,19060,176310,1807181, 20330788,249052161,3299941145,47024161317, 717118460090,11653174976468,201017268344078, 3668565147279423,70619879085128903, 1430052551473860292]

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Last modified April 24 13:24 EDT 2024. Contains 371955 sequences. (Running on oeis4.)