

A107121


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.


2




OFFSET

1,1


COMMENTS

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).


LINKS

Table of n, a(n) for n=1..4.


EXAMPLE

14738827 is in the sequence because 14738827=prime(prime((1*4*7*3*8*8*2*7)).


MATHEMATICA

Do[h= IntegerDigits[Prime[m]]; l = Length[h]; If[Min[h] > 0 && m == Prime[Product[h[[k]], {k, l}]], Print[Prime [m]]], {m, 20000000}]


CROSSREFS

Cf. A097223, A107120, A107122.
Sequence in context: A142832 A277989 A138956 * A101734 A059025 A267200
Adjacent sequences: A107118 A107119 A107120 * A107122 A107123 A107124


KEYWORD

base,nonn


AUTHOR

Farideh Firoozbakht, May 13 2005


STATUS

approved



