n,k,m=map(int,input().split())
big2={}
for b in range(3,20):
 i=1
 while 1:
  x=1
  for j in range(b):x*=i+j*k
  if x>n:break
  big2.setdefault(x,0);big2[x]+=1;i+=1
count_2=0
ng=10**9
while-~count_2<ng:
 m=count_2+ng>>1
 if(m+k)*m>n:ng=m
 else:count_2=m
for i in big2:y=round(-k/2+((k/2)**2+i)**0.5);g=y*(y+k)==i;big2[i]+=g;count_2-=g
print(sum(big2[i]==m for i in big2)+[0,count_2][m==1])