OFFSET
1,1
FORMULA
Conjecture: a(n)= +4*a(n-1) -6*a(n-2) +5*a(n-3) -5*a(n-4) +6*a(n-5) -4*a(n-6) +a(n-7). G.f. x*(-5-11*x-7*x^2-5*x^3+x^4) / ( (1+x+x^2)*(x-1)^5 ). - R. J. Mathar, Oct 08 2011
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved