OFFSET
1,2
FORMULA
a(n) = +9*a(n-1) +11*a(n-2) -10*a(n-3). [Joerg Arndt, May 14 2011]
a(n)=10*a(n-1)+F(n) for n=odd and a(n)=10*a(n-1)-F(n) for n=even, with a(0)= 0 and F(n) is the n-th Fibonacci number
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Mark Dols, Aug 31 2009
STATUS
approved