A158827 as tables, graphs or sounds

A158827 formatted as a simple table:

`n`		`a(n)`
`1`		`1`
`2`		`4`
`3`		`20`
`4`		`110`
`5`		`640`
`6`		`3870`
`7`		`24084`
`8`		`153306`
`9`		`993978`
`10`		`6544242`
`11`		`43652340`
`12`		`294469974`
`13`		`2006018748`
`14`		`13784115468`
`15`		`95444016984`
`16`		`665407010349`
`17`		`4667570034444`
`18`		`32922870719664`
`19`		`233389493503968`
`20`		`1662048903052380`
`21`		`11885333877149532`

[1,4,20,110,640,3870,24084,153306,993978,6544242, 43652340,294469974,2006018748,13784115468, 95444016984,665407010349,4667570034444, 32922870719664,233389493503968,1662048903052380, 11885333877149532]

Last modified December 15 00:47 EST 2009. Contains 170825 sequences.

AT&T Labs Research