A002638 - OEIS

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A002638 as a simple table

`n`		`a(n)`
`1`		`-1`
`2`		`1`
`3`		`2`
`4`		`3`
`5`		`12`
`6`		`52`
`7`		`456`
`8`		`6873`
`9`		`191532`
`10`		`9733032`
`11`		`903753248`
`12`		`154108311046`
`13`		`48542114686912`
`14`		`28401423719121392`
`15`		`31021002160355166800`
`16`		`63530415842308265086523`
`17`		`244912778438520759443245824`
`18`		`1783398846284777975419599903948`
`19`		`24605641171260376770598003978281472`

[-1,1,2,3,12,52,456,6873,191532,9733032,903753248, 154108311046,48542114686912,28401423719121392, 31021002160355166800,63530415842308265086523, 244912778438520759443245824, 1783398846284777975419599903948, 24605641171260376770598003978281472]

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Last modified May 7 12:11 EDT 2024. Contains 372303 sequences. (Running on oeis4.)