A002520 as tables, graphs or sounds

A002520 formatted as a simple table:

`n`		`a(n)`
`0`		`1`
`1`		`0`
`2`		`0`
`3`		`2240`
`4`		`98280`
`5`		`1790208`
`6`		`19138560`
`7`		`141920640`
`8`		`805208040`
`9`		`3723722240`
`10`		`14651449344`
`11`		`50573436480`
`12`		`156717687840`
`13`		`443691198720`
`14`		`1162883174400`
`15`		`2851049534592`
`16`		`6596666916840`
`17`		`14509544394240`
`18`		`30507984568320`

[1,0,0,2240,98280,1790208,19138560,141920640, 805208040,3723722240,14651449344,50573436480, 156717687840,443691198720,1162883174400, 2851049534592,6596666916840,14509544394240, 30507984568320]

Last modified December 5 08:23 EST 2009. Contains 170348 sequences.

AT&T Labs Research