A052881 as tables, graphs or sounds

A052881 formatted as a simple table:

`n`		`a(n)`
`0`		`0`
`1`		`0`
`2`		`2`
`3`		`9`
`4`		`44`
`5`		`250`
`6`		`1644`
`7`		`12348`
`8`		`104544`
`9`		`986256`
`10`		`10265760`
`11`		`116915040`
`12`		`1446526080`
`13`		`19323757440`
`14`		`277238626560`
`15`		`4251984710400`
`16`		`69426608025600`
`17`		`1202482800691200`
`18`		`22021300630425600`
`19`		`425162773111910400`

[0,0,2,9,44,250,1644,12348,104544,986256,10265760, 116915040,1446526080,19323757440,277238626560, 4251984710400,69426608025600,1202482800691200, 22021300630425600,425162773111910400]

Last modified December 3 22:15 EST 2009. Contains 170310 sequences.

AT&T Labs Research