#include <iostream>
#include <string>
#include <algorithm>
int** sumArray;
bool* memeArray;
int height;
int width;
int treesWanted;
int out = 0;
int countTrees(int x, int y, int s);
int maxS;
void search(int roiX1, int roiY1, int roiX2, int roiY2, int s);
int main() {
std::cin >> height >> width >> treesWanted >> std::ws;
maxS = std::min(width - 1, height - 1);
memeArray = new bool[height*width*maxS];
memset(memeArray, false, (height+1)*(width+1)*(maxS+2)*sizeof(bool*));
sumArray = new int*[height];
{
std::string line;
int currentRowSum = 0;
for (int y = 0; y < height; y++) {
sumArray[y] = new int[width];
memset(sumArray[y], 0, width*sizeof(sumArray[y]));
std::getline(std::cin, line);
currentRowSum = 0;
for (int x = 0; x < width; x++) {
if (line[x] == '*') {
currentRowSum++;
}
sumArray[y][x] = sumArray[std::max(0, y - 1)][x] + currentRowSum;
}
}
}
search(0, 0, width - 1, height - 1, maxS);
std::cout << out;
getchar();
return 0;
}
void search(int roiX1, int roiY1, int roiX2, int roiY2, int s) {
int c;
for (int y = roiY1; y <= roiY2 - s; y++) {
for (int x = roiX1; x <= roiX2 - s; x++) {
c = countTrees(x, y, s);
//std::cout << c << std::endl;
if (c > treesWanted && s > 0) search(x, y, x + s, y + s, s - 1);
else if (c == treesWanted && !memeArray[(y+1)*width*height+(x+1)*height+maxS]) {
//std::cout << "x: " << x << " y: " << y << " s: " << s << std::endl;
memeArray[(y + 1)*width*height + (x + 1)*height + maxS] = true;
out++;
if (s > 0) {
search(x, y, x + s, y + s, s - 1);
}
}
}
}
}
int countTrees(int x, int y, int s) {
int trees = sumArray[y + s][x + s];
if (x != 0) trees -= sumArray[y + s][x - 1];
if (y != 0) trees -= sumArray[y - 1][x + s];
if (x != 0 && y != 0) trees += sumArray[y-1][x-1];
return trees;
}