N,K=map(int,input().split())
mod=998244353
u=[1]*(2*N+1)
u2=[1]*(2*N+1)
for i in range(1,2*N+1):
  u[i]=u[i-1]*i
  u[i]%=mod
  u2[i]=pow(u[i],-1,mod)
def ncm(x,y):
  if y<0 or y>x:
    return 0
  ans=u[x]*u2[y]
  ans%=mod
  ans*=u2[x-y]
  ans%=mod
  return ans
result=0
for x in range(2*N+1):
  z=2*N-x
  pos=(x-z)%(2*K+4)
  if pos==2*K+2:
    result-=ncm(2*N,x)
  if pos==0:
    result+=ncm(2*N,x)
result2=0
for x in range(2*N+1):
  z=2*N-x
  pos=(x-z)%(2*K+2)
  if pos==2*K:
    result2-=ncm(2*N,x)
  if pos==0:
    result2+=ncm(2*N,x)
result-=result2
result%=mod
print(result)