N,V=map(int,input().split())
C=[0]+list(map(int,input().split()))
for v in range(1,N+1):
    C[v]+=C[v-1]
V=max(V,N)
S=N*N
inf=1<<60
dp=[inf]*(S+1)
dp[N]=C[N]
for v in range(1,N+1):
    c=C[v]
    for s in range(v,S+1):
        dp[s]=min(dp[s],dp[s-v]+c)
ans=inf
for s in range(S+1):
    for v in range(1,N+1):
        c=C[v]
        if s<=V and (V-s)%v==0:
            ans=min(ans,dp[s]+(V-s)//v*c)
print(ans)