on-restart-benchmarks/software/minizinc/docs/chi/examples/magic-series.mzn

int: n;
array[0..n-1] of var 0..n: s;

constraint forall(i in 0..n-1) (
   s[i] = (sum(j in 0..n-1)(bool2int(s[j]=i))));

solve satisfy;   

output [ "s = \(s);\n" ] ;