|
%I #5 Mar 30 2012 17:37:43
%S 461,264961,9548491,14738827
%N Numbers n such that n=prime(prime(d_1*d_2*...*d_k)) where d_1 d_2 ... d_k is the decimal expansion of n.
%C If n is in the sequence then pi(n) = prime(d_1*d_2* ...d_k) where d_1 d_2 ... d_k is the decimal expansion of n, so this sequence is a subsequence of A107120. There is no further term up to prime(2*10^7).
%e 14738827 is in the sequence because 14738827=prime(prime((1*4*7*3*8*8*2*7)).
%t Do[h= IntegerDigits[Prime[m]];l = Length[h];If[Min[h] > 0 && m == Prime[Product[h[[k]], {k, l}]], Print[Prime [m]]], {m, 20000000}]
%Y Cf. A097223, A107120, A107122.
%K base,nonn
%O 1,1
%A _Farideh Firoozbakht_, May 13 2005
| 