import sys import numpy as np read = sys.stdin.buffer.read readline = sys.stdin.buffer.readline readlines = sys.stdin.buffer.readlines MOD = 10**9 + 7 def compute_next_status(status, vertical): status = list(status) deg = [0] * 4 for i, x in enumerate(status): if x != 0: deg[i] = 1 loop = False for i in range(3): if vertical & (1 << i): deg[i] += 1 deg[i+1] += 1 if status[i] == status[i+1] != 0: if loop: return None loop = True status[i] = status[i+1] = 0 continue if status[i] == status[i+1] == 0: status[i] = status[i+1] = max(status) + 1 elif status[i] != 0 and status[i+1] == 0: status[i+1] = status[i] elif status[i+1] != 0 and status[i] == 0: status[i] = status[i+1] else: n, m = status[i:i+2] n, m = max(n, m), min(n, m) for v in range(4): if status[v] == m: status[v] = n if loop: if any(x in [1,3] for x in deg): return None return (0,0,0,0) if any(x >= 3 for x in deg): return None for v in range(4): if deg[v] != 1: status[v] = 0 for n, k in enumerate(set(status + [0])): if k == 0: continue for v in range(4): if status[v] == k: status[v] = n return tuple(status) visited = set([(0,0,0,0)]) q = [(0,0,0,0)] edges = [] while q: v = q.pop() for i in range(8): w = compute_next_status(v, i) if w is None: continue edges.append((v,w)) if w in visited: continue visited.add(w) q.append(w) visited L = len(visited) + 1 A = np.zeros((L,L), dtype=object) v_to_i = {v:i for i,v in enumerate(visited)} i0 = v_to_i[(0,0,0,0)] i_end = L - 1 for v,w in edges: iv, iw = v_to_i[v], v_to_i[w] if iv != i0 and iw == i0: iw = i_end A[iw, iv] = 1 A[i_end, i_end] += 1 def mult_mod(A, B, MOD=MOD): mask = (1<<15) - 1 A1, A2 = A>>15, A & mask B1, B2 = B>>15, B&mask X = np.dot(A1, B1) % MOD Z = np.dot(A2, B2) % MOD Y = (np.dot(A1+A2,B1+B2)-X-Z)%MOD return ((X<<30)+(Y<<15)+Z)%MOD def matrix_power(A, n, MOD=MOD): if n == 1: return A B = matrix_power(A, n//2) B = mult_mod(B, B) if n & 1: B = mult_mod(A, B) return B MOD = 10**9 + 7 N = int(read()) print(matrix_power(A, N + 1)[i_end, i0])