If f(x)=x(x+1)(x+2)(x+3), then find the value of f(0)+f(−1)+f(−2)+f(−3).
f(x)=x^(x+1)*(x+2)^(x+3)
f(0)=0^(0+1)*(0+2)^(0+3)
f(0)=0^1*2^3
f(0)=0*8
f(0)=0
f(-1)=1
f(-2)=0
f(-3)=1/9
f(0)+f(-1)+f(-2)+f(-3)=10/9
0+1+0+(1/9)=10/9
+537 
