#!/usr/bin/env python3
def main():
    n, k = map(int, input().split())
    a = [int(input()) for _ in range(n)]
    a.sort()

    # dp[k][i][j] = number of ways to select k valid problems such that the last two are i and j
    # starts with dp[2], only save last layer
    dp = [[1 for _ in range(n)] for _ in range(n)]

    for _ in range(k - 2):
        ndp = [[0 for _ in range(n)] for _ in range(n)]
        for i in range(n):
            for j in range(i + 1, n):
                for k in range(j + 1, n):
                    if a[i] + a[j] >= a[k]:
                        ndp[j][k] += dp[i][j]

        dp = ndp

    ans = sum(sum(row) for row in dp)
    print(ans)


if __name__ == "__main__":
    main()