# input
import sys
input = sys.stdin.readline
II = lambda : int(input())
MI = lambda : map(int, input().split())
LI = lambda : [int(a) for a in input().split()]
SI = lambda : input().rstrip()
LLI = lambda n : [[int(a) for a in input().split()] for _ in range(n)]
LSI = lambda n : [input().rstrip() for _ in range(n)]
MI_1 = lambda : map(lambda x:int(x)-1, input().split())
LI_1 = lambda : [int(a)-1 for a in input().split()]

mod = 998244353
inf = 1001001001001001001
ordalp = lambda s : ord(s)-65 if s.isupper() else ord(s)-97
ordallalp = lambda s : ord(s)-39 if s.isupper() else ord(s)-97
yes = lambda : print("Yes")
no = lambda : print("No")
yn = lambda flag : print("Yes" if flag else "No")

prinf = lambda ans : print(ans if ans < 1000001001001001001 else -1)
alplow = "abcdefghijklmnopqrstuvwxyz"
alpup = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
alpall = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
URDL = {'U':(-1,0), 'R':(0,1), 'D':(1,0), 'L':(0,-1)}
DIR_4 = [[-1,0],[0,1],[1,0],[0,-1]]
DIR_8 = [[-1,0],[-1,1],[0,1],[1,1],[1,0],[1,-1],[0,-1],[-1,-1]]
DIR_BISHOP = [[-1,1],[1,1],[1,-1],[-1,-1]]
prime60 = [2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59]
sys.set_int_max_str_digits(0)
# sys.setrecursionlimit(10**6)
# import pypyjit
# pypyjit.set_param('max_unroll_recursion=-1')

from collections import defaultdict,deque
from heapq import heappop,heappush
from bisect import bisect_left,bisect_right
DD = defaultdict
BSL = bisect_left
BSR = bisect_right

"""
(u, v) -> (v, s - u) まで O(N^2) でも可能

既にあるのに mergeなら？
(max, s - osum)
"""

n = II()
par = [-1] + LI_1()
siz = [1] * n
dp = [[1] for i in range(n)]

for u in reversed(range(n)):
    # dp[u] の前処理
    t = dp[u]
    t += [0] * (siz[u] + 1 - len(t))
    for i in range(siz[u]):
        t[i+1] = (t[i+1] + t[i]) % mod
    
    # print(u, t)
    if u == 0:
        print(sum(t) % mod)
        break
    
    # 部分木の決め方
    p = par[u]
    siz[p] += siz[u]
    
    s = dp[p]
    # t = dp[u]
    ndp = [0] * (len(s) + len(t) - 1)
    for i in range(len(s)):
        for j in range(len(t)):
            ndp[i+j] += s[i] * t[j] % mod
    
    dp[p] = ndp