C (gcc), 187 bytes

*D,E;r(a,n,g,e){e=g=0;if(!a){for(g=0;e|=D[g]==g,g<E;g++)for(n=0;n<g;)e|=D[n++]==D[g];for(g=e*E;g<E;)printf("%d ",D[g++]);e||puts("");}for(a--;g<E;r(a))D[a]=g++;}y(_){int M[E=_];D=M;r(_);} 

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C (gcc), 187 180 bytes

• Saved seven bytes thanks to ceilingcat.

*D,E;r(a,n,g,e){e=g=0;if(!a--){for(;e|=D[g]==g,g<E;g++)for(n=g;n--;)e|=D[n]==D[g];for(g*=e;g<E;)printf("%d ",D[g++]);e||puts("");}for(;g<E;r(a))D[a]=g++;}y(_){int M[E=_];D=M;r(_);} 

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C (gcc), 187 bytes

*N,n;g(k,i,j,x){x=j=0;if(!k){for(j=0;x|=N[j]==j,j<n;j++)for(i=0;i<j;)x|=N[i++]==N[j];for(j=x*n;j<n;)printf("%d ",N[j++]);x||puts("");}for(k--;j<n;g(k))N[k]=j++;}f(m){int M[n=m];N=M;g(m);} 

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C (gcc), 187 bytes

*D,E;r(a,n,g,e){e=g=0;if(!a){for(g=0;e|=D[g]==g,g<E;g++)for(n=0;n<g;)e|=D[n++]==D[g];for(g=e*E;g<E;)printf("%d ",D[g++]);e||puts("");}for(a--;g<E;r(a))D[a]=g++;}y(_){int M[E=_];D=M;r(_);} 

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