OFFSET
1,2
LINKS
Andrew Howroyd, Table of n, a(n) for n = 1..100
EXAMPLE
2^2 - 1*3 = 1 = a(1).
4^4 - 2*3*5*6 = 256 - 180 = 76 = a(2).
6^6 - 3*4*5*7*8*9 = 46656 - 30240 = 16416 = a(3).
8^8 - 4*5*6*7*9*10*11*12 = 16777216 - 9979200 = 6798016 = a(4).
...
MAPLE
a:=n->(2*n)^(2*n)-(2*n-1)!*(3*n)!/(n-1)!/(2*n)!: seq(a(n), n=1..13); # (Emeric Deutsch)
MATHEMATICA
Table[(2n)^(2n)-(2n-1)!(3n)!/((n-1)!(2n)!), {n, 12}] (* Harvey P. Dale, Jul 06 2011 *)
PROG
(PARI) a(n)={(2*n)^(2*n) - (2*n-1)!*(3*n)!/((n-1)!*(2*n)!)} \\ Andrew Howroyd, Nov 09 2019
CROSSREFS
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Aug 16 2005
EXTENSIONS
More terms from Emeric Deutsch, Aug 27 2005
Terms a(12) and beyond from Andrew Howroyd, Nov 09 2019
STATUS
approved