A221957 - OEIS

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A221957 as a simple table

`n`		`a(n)`
`0`		`1`
`1`		`2`
`2`		`7`
`3`		`31`
`4`		`159`
`5`		`921`
`6`		`5988`
`7`		`43632`
`8`		`355491`
`9`		`3223729`
`10`		`32329668`
`11`		`355979064`
`12`		`4273100846`
`13`		`55555511298`
`14`		`777797216472`
`15`		`11667035805840`
`16`		`186672873433635`
`17`		`3173440015174905`
`18`		`57121924810715940`
`19`		`1085316589076234760`
`20`		`21706331850447959610`
`21`		`455832969128536089030`

[1,2,7,31,159,921,5988,43632,355491,3223729, 32329668,355979064,4273100846,55555511298, 777797216472,11667035805840,186672873433635, 3173440015174905,57121924810715940, 1085316589076234760,21706331850447959610, 455832969128536089030]

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Last modified April 16 01:01 EDT 2024. Contains 371696 sequences. (Running on oeis4.)