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Numbers n such that n=P(d_1*d_2*...*d_k) + P(d_1+d_2+...+d_k) where d_1 d_2 ... d_k is the decimal expansion of n and P(i) is the i-th prime.
2

%I #4 Mar 30 2012 17:37:42

%S 82,92,194,149868

%N Numbers n such that n=P(d_1*d_2*...*d_k) + P(d_1+d_2+...+d_k) where d_1 d_2 ... d_k is the decimal expansion of n and P(i) is the i-th prime.

%C All terms of this sequence are even. Next term (if it exists) is greater than 25000000.

%e 149868 is in the sequence because 149868=149717+151=P(1*4*9*8*6*8)+P(1+4+9+8+6+8).

%t Do[h=IntegerDigits[n];l=Length[h];If[ !MemberQ[h, 0]&& n==Prime[Product[h[[k]], {k, l}]]+Prime[Sum[h[[k]], {k, l}]], Print[n]], {n, 25000000}]

%Y Cf. A099068, A099069.

%K base,more,nonn

%O 1,1

%A _Farideh Firoozbakht_, Oct 08 2004