N,K = map(int,input().split())
a = list(map(int,input().split()))

a.sort()
P = 10 ** 9 + 7
dp = [0] * (K+1)
dp[0] = 1
for i in range(N):
    nx = [0] * (K + 1)
    S = [0] * (K + 2)
    for j in range(K+1):
        S[j+1] = (S[j] + dp[j]) % P
    for j in range(K+1):
        tmp = S[j+1] - S[max(0,j-i)]
        nx[j] += tmp

    
    for u in range(K+1):
        nx[u] %= P
    dp = nx
ans = 0
for i in dp:
    ans = (ans + i) % P
print(ans)