This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A262447 #11 May 31 2018 08:17:06
%S A262447 13,53,73,131,199,277,281,283,313,353,641,643,647,701,773,839,887,977,
%T A262447 1033,1103,1117,1163,1187,1223,1259,1409,1433,1439,1487,1489,1583,
%U A262447 1721,1913,1931,2239,2243,2269,2309,2371,2441,2473,2477,2621,2683,2707,2797,2843,2851,2953,3049,3137,3257,3307,3499,3511,3613,3659,3769,3779,3911
%N A262447 Primes p such that pi(p^2) = pi(q^2) + pi(r^2) for some distinct primes q and r.
%C A262447 Conjecture: The sequence has infinitely many terms.
%C A262447 See also A262408 and A262443 for related conjectures.
%D A262447 Zhi-Wei Sun, Problems on combinatorial properties of primes, in: M. Kaneko, S. Kanemitsu and J. Liu (eds.), Number Theory: Plowing and Starring through High Wave Forms, Proc. 7th China-Japan Seminar (Fukuoka, Oct. 28 - Nov. 1, 2013), Ser. Number Theory Appl., Vol. 11, World Sci., Singapore, 2015, pp. 169-187.
%H A262447 Chai Wah Wu, <a href="/A262447/b262447.txt">Table of n, a(n) for n = 1..10000</a> (n = 1..500 from Zhi-Wei Sun)
%H A262447 Zhi-Wei Sun, <a href="http://arxiv.org/abs/1402.6641">Problems on combinatorial properties of primes</a>, arXiv:1402.6641 [math.NT], 2014.
%e A262447 a(1) = 13 since pi(13^2) = pi(169) = 39 = 9 + 30 = pi(5^2) + pi(11^2) with 13, 5 and 11 distinct primes.
%t A262447 f[n_]:=PrimePi[Prime[n]^2]
%t A262447 T[n_]:=Table[f[k],{k,1,n}]
%t A262447 n=0;Do[Do[If[2*f[k]>=f[m],Goto[aa]];If[MemberQ[T[m-1],f[m]-f[k]],n=n+1;Print[n," ",Prime[m]];Goto[aa]];Continue,{k,1,m-1}];Label[aa];Continue,{m,1,541}]
%Y A262447 Cf. A000040, A000290, A000720, A262408, A262443.
%K A262447 nonn
%O A262447 1,1
%A A262447 _Zhi-Wei Sun_, Sep 23 2015