%I #2 Mar 30 2012 17:37:48
%S 14,67673,25688777
%N Numbers n such that n=prime(P)+sigma(P), where P is product of digits of n.
%C The product of the digits of next term (if it exists) is greater than 2*10^8.
%e 25688777=prime(2*5*6*8*8*7*7*7)+sigma(2*5*6*8*8*7*7*7), so 25688777 is in the
%e sequence.
%t Do[If[n=Prime[m]+DivisorSigma[1,m];m==Apply[Times,IntegerDigits[n]],Print[n]],
%t {m,200000000}]
%Y Cf. A000040, A000203, A164323, A164324.
%K base,more,nonn,bref
%O 1,1
%A _Farideh Firoozbakht_, Aug 13 2009
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