OFFSET
2,1
FORMULA
a(n)=18*a(n-1)-146*a(n-2)+706*a(n-3)-2268*a(n-4)+5102*a(n-5)-8246*a(n-6)+9654*a(n-7)-8131*a(n-8)+4808*a(n-9)-1896*a(n-10)+448*a(n-11)-48*a(n-12)
a(n)= 1/18*n^6+1/2*n^5+169/72*n^4-n^3*2^(n+1)+29/4*n^3-9*n^2*2^n+ 1123/72*n^2 -37*n*2^n+ 101/4*n-90*2^n+135/2*3^n+45/2
G.f.: GF3(z;m=2) = z^2*(-6+29*z+31*z^2-283*z^3+245*z^4+298*z^5-286*z^6-108*z^7)/((1-z)^7*(1-2*z)^4*(1-3*z))
CROSSREFS
KEYWORD
easy,sign
AUTHOR
Johannes W. Meijer, Feb 20 2009
STATUS
approved