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Least positive integer m such that m + n divides pi(m)^2 + pi(n)^2, where pi(x) denotes the number of primes not exceeding x.
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%I #12 Jan 03 2018 19:42:47

%S 1,3,1,4,12,11,1,8,7,16,2,5,26,25,24,4,228,227,46,45,44,43,16,6,5,1,

%T 27,26,45,44,12526,12525,12524,12523,2970,502,351,350,46,45,236,235,

%U 10,9,8,4,1078,1077,576,575,574,198,63,62,61,176,16,10,362,70

%N Least positive integer m such that m + n divides pi(m)^2 + pi(n)^2, where pi(x) denotes the number of primes not exceeding x.

%C Conjecture: a(n) exists for any n > 0.

%H Chai Wah Wu, <a href="/A248044/b248044.txt">Table of n, a(n) for n = 1..10000</a> (n = 1..1387 from Zhi-Wei Sun)

%H Zhi-Wei Sun, <a href="http://arxiv.org/abs/1409.5685">A new theorem on the prime-counting function</a>, arXiv:1409.5685, 2014.

%e a(5) = 12 since 12 + 5 = 17 divides pi(12)^2 + pi(5)^2 = 5^2 + 3^2 = 34.

%t Do[m=1;Label[aa];If[Mod[PrimePi[m]^2+PrimePi[n]^2,m+n]==0,Print[n," ",m];Goto[bb]];m=m+1;Goto[aa];Label[bb];Continue,{n,1,60}]

%Y Cf. A000720, A247824, A247975, A248035, A248036.

%K nonn,look

%O 1,2

%A _Zhi-Wei Sun_, Sep 30 2014