题解 | 牛牛学数列6
牛牛学数列6
https://www.nowcoder.com/practice/b6321648517247b2ac2e2f80cbc63ae1
x= int(input())
def function_A(x):
A = [0]*(x+1)
if x >= 1:
A[1] = 0
if x >= 2:
A[2] = 1
if x >= 3:
A[3] = 1
for i in range(4,x+1):
A[i] = A[i-3]+2*A[i-2]+A[i-1]
return A
A = function_A(x)
print(A[x])
