import sys
input = sys.stdin.readline

N,L,U=map(int,input().split())

mod=998244353

FACT=[1]
for i in range(1,5*10**5+1):
    FACT.append(FACT[-1]*i%mod)

FACT_INV=[pow(FACT[-1],mod-2,mod)]
for i in range(5*10**5,0,-1):
    FACT_INV.append(FACT_INV[-1]*i%mod)

FACT_INV.reverse()

def Combi(a,b):
    if 0<=b<=a:
        return FACT[a]*FACT_INV[b]%mod*FACT_INV[a-b]%mod
    else:
        return 0
k=U+1
ANS=0
for i in range(L,U+1):
    M=i+N
    ANS+=Combi(M+N-1,N-1)
    ANS-=Combi(N-1+M,N+k)
    ANS%=mod

print(ANS%mod)