OFFSET
1,2
FORMULA
a(n) = ( (2n)^n+n*(n-1)^n ) /(n+1).
EXAMPLE
a(5) = determinant of the (5 X 5) matrix = 17520.
[ 5 -5 -5 -5 -5 ]
[ 1 5 -5 -5 -5 ]
[ 1 1 5 -5 -5 ]
[ 1 1 1 5 -5 ]
[ 1 1 1 1 5 ]
MAPLE
CROSSREFS
KEYWORD
nonn
AUTHOR
Michel Lagneau, May 04 2010
STATUS
approved