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%I #7 Dec 14 2015 17:54:20
%S 2,5,7,11,19
%N Prime permutational numbers A134640.
%C Conjecture: This sequence is finite and complete.
%C The conjecture is correct: in base 2k permutational numbers are divisible by 2k-1 and in base 2k+1 permutational numbers are divisible by k. Hence it suffices to check bases up to 3. - _Charles R Greathouse IV_, Dec 14 2015
%t a = {}; b = {}; Do[AppendTo[b, n]; w =Permutations[b]; Do[j = FromDigits[w[[m]], n + 1]; If[PrimeQ[j], AppendTo[a, j]], {m, 1, Length[w]}], {n, 0, 10}]; a (*Artur Jasinski*)
%o (PARI) for(b=2,3, for(i=0,b!-1, p=fromdigits(apply(j->j-1, numtoperm(b,i)),b); if(isprime(p), print1(p", ")))) \\ _Charles R Greathouse IV_, Dec 14 2015
%Y Cf. A134640.
%K nonn,fini,full
%O 1,1
%A _Artur Jasinski_, Nov 05 2007
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