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%I #21 Aug 06 2022 08:18:59
%S 16,53,185,238,2495,19775,4878937
%N Numbers k such that k = prime(P) + pi(P), where P is product of digits of k.
%C The product of the digits of next term (if it exists) is greater than 3*10^8.
%C a(8) > 10^12, if it exists. - _Chai Wah Wu_, Apr 24 2018
%C a(8) > 10^16, if it exists. - _Chai Wah Wu_, Apr 21 2021
%e 16 = prime(1*6) + pi(1*6), so 16 is in the sequence.
%e 4878937 = prime(4*8*7*8*9*3*7) + pi(4*8*7*8*9*3*7), so 4878937 is in the sequence.
%t Do[If[n=Prime[m]+PrimePi[m];m==Apply[Times,IntegerDigits[n]],Print[n]],{m,300000000}]
%Y Cf. A000040, A000720, A007954, A164322, A164323.
%K nonn,base,more,fini
%O 1,1
%A _Farideh Firoozbakht_, Aug 13 2009
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