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%I #13 Dec 14 2014 02:04:11
%S 1,1,1,1,1,2,2,1,1,1,2,2,1,1,1,1,1,1,1,2,2,2,1,1,2,1,1,2,1,3,2,3,3,2,
%T 4,1,3,3,3,3,4,2,2,2,4,3,1,1,1,1,1,2,2,2,1,1,1,2,2,2,2,2,1,3,2,3,2,3,
%U 2,2,1,3,2,3,4,1,3,4,1,1,4,2,1,1,2,1,1,2,2,2,2,2,1,4,1,1,1,2,1,1,2,1,2,2,3
%N Number of different primes that can be formed by permuting digits of n-th prime.
%C Leading zeros not permitted, so, e.g., prime(27) = 103 but a(27) = 1 even though 13 and 31 are both primes. - _Harvey P. Dale_, Dec 17 2012
%e a(75)=4 because the digits in 379 may be arranged to form a total of 4 primes: 379, 397, 739 and 937.
%t ndp[n_]:=Module[{pers=FromDigits/@Permutations[IntegerDigits[n]]}, Count[ pers,_?(IntegerLength[#]==IntegerLength[n]&&PrimeQ[#]&)]]; ndp/@ Prime[ Range[110]] (* _Harvey P. Dale_, Dec 17 2012 *)
%Y A039999, A046810.
%K base,easy,nonn
%O 2,6
%A _Enoch Haga_, Mar 16 2000
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