OFFSET
0,2
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..1000
FORMULA
G.f.: (8*x^2+4*x+3)*x/(1-x)^7.
a(n) = n*(n+1)*(n+2)*(n+3)*(n^2+n+4)/48.
EXAMPLE
a(1) = 3: .1-2. .1.2. .1-2.
. .|.|. .|X|. ..X..
. .3-4. .3.4. .3-4.
MAPLE
a:= n-> (24+(50+(41+(21+(7+n)*n)*n)*n)*n)*n/48:
seq (a(n), n=0..40);
CROSSREFS
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Aug 23 2012
STATUS
approved