A026993 - OEIS

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A026993 as a simple table

`n`		`a(n)`
`2`		`1`
`3`		`6`
`4`		`32`
`5`		`180`
`6`		`984`
`7`		`4606`
`8`		`22689`
`9`		`114992`
`10`		`567129`
`11`		`2576582`
`12`		`12586319`
`13`		`63131004`
`14`		`305635176`
`15`		`1384074886`
`16`		`6739962365`
`17`		`33708050180`
`18`		`162468169385`
`19`		`737652413014`
`20`		`3588021213950`
`21`		`17917172173846`
`22`		`86273708463456`
`23`		`393163075111278`
`24`		`1911781914938634`
`25`		`9536792007640980`
`26`		`45924386118166540`

[1,6,32,180,984,4606,22689,114992,567129,2576582, 12586319,63131004,305635176,1384074886,6739962365, 33708050180,162468169385,737652413014, 3588021213950,17917172173846,86273708463456, 393163075111278,1911781914938634,9536792007640980, 45924386118166540]

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Last modified December 3 03:10 EST 2023. Contains 367531 sequences. (Running on oeis4.)