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Numbers n such that pi(n)=reversal(n)-n.
2

%I #6 Aug 08 2019 07:42:10

%S 1,23,526,536,1802,4735,17191,38524,235652,36235483,1086331411,

%T 5316125655,7202194357,49294058315,327040088933

%N Numbers n such that pi(n)=reversal(n)-n.

%C a(16) > 10^13. - _Giovanni Resta_, Aug 08 2019

%e 36235483 is in the sequence because pi(36235483)=2217780= 38453263-36235483=reversal(36235483)-36235483.

%t Do[If[PrimePi[n]==FromDigits[Reverse[IntegerDigits[n]]] -n,Print[n]],{n,30000000}]

%Y Cf. A072393, A100415.

%K nonn,base,more

%O 1,2

%A _Farideh Firoozbakht_, Feb 03 2006

%E a(11)-a(15) from _Giovanni Resta_, Aug 08 2019