Find the sum of the functions
Source: Turkey NMO 2008 Problem 4
December 2, 2008
functionalgebra unsolvedalgebra
Problem Statement
satisfy the given conditions
f(0,0)\equal{}1 , f(0,1)\equal{}1 ,
f(0,k)\equal{}0 and
and , f(n,k)\equal{}f(n\minus{}1,k)\plus{}f(n\minus{}1,k\minus{}2n)
find the sum \displaystyle\sum_{k\equal{}0}^{\binom{2009}{2}}f(2008,k)