import sys
import math

def main():
    N, K, M = map(int, sys.stdin.readline().split())
    answer = 0

    count = dict()

    s = 2
    while True:
        min_prod = 1
        for i in range(s):
            term = 1 + i * K
            if term > N:
                min_prod = N + 1
                break
            if min_prod > N // term:
                min_prod = N + 1
                break
            min_prod *= term
            if min_prod > N:
                break
        if min_prod > N:
            break

        low = 1
        high = N
        best_A = 0
        while low <= high:
            mid = (low + high) // 2
            product = 1
            valid = True
            for i in range(s):
                term = mid + i * K
                if term > N:
                    valid = False
                    break
                if product > N // term:
                    valid = False
                    break
                product *= term
                if product > N:
                    valid = False
                    break
            if valid:
                best_A = mid
                low = mid + 1
            else:
                high = mid - 1

        if best_A == 0:
            s += 1
            continue

        for A in range(1, best_A + 1):
            product = 1
            for i in range(s):
                term = A + i * K
                product *= term
                if product > N:
                    product = None
                    break
            if product is not None and product <= N:
                if product in count:
                    count[product] += 1
                else:
                    count[product] = 1
        s += 1

    answer = sum(1 for v in count.values() if v == M)
    print(answer)

if __name__ == '__main__':
    main()