n,p=map(int,input().split())
M=998244353
fa=[1,1]
fb=[1,1]
for i in range(2,n+1):
  fa+=[fa[-1]*i%M]
  fb+=[fb[-1]*(M//i)*fb[M%i]*fa[M%i-1]*(-1)%M]
if n<p:
  print((fa[n]-1)%M)
  exit()
a=fa[n]
for i in range(n//p+1):
  a-=fa[n]*pow(fb[p],i,M)*fb[i]*fb[n-p*i]*pow(fa[p-1],i,M)
  a%=M
print(a)