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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.

A226539 Numbers which are the sum of two squared primes in exactly two ways (ignoring order).

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%I A226539 #29 Dec 15 2019 11:34:11
%S A226539 338,410,578,650,890,1010,1130,1490,1730,1802,1898,1970,2330,2378,
%T A226539 2738,3050,3170,3530,3650,3842,3890,4010,4658,4850,5018,5090,5162,
%U A226539 5402,5450,5570,5618,5690,5858,6170,6410,6530,6698,7010,7178,7202,7250,7850,7970,8090
%N A226539 Numbers which are the sum of two squared primes in exactly two ways (ignoring order).
%D A226539 Stan Wagon, Mathematica in Action, Springer, 2000 (2nd ed.), Ch. 17.5, pp. 375-378.
%H A226539 T. D. Noe, <a href="/A226539/b226539.txt">Table of n, a(n) for n = 1..10000</a>
%e A226539 338 = 7^2 + 17^2 = 13^2 + 13^2;
%e A226539 410 = 7^2 + 19^2 = 11^2 + 17^2.
%p A226539 Prime2PairsSum := p -> select(x ->`if`(andmap(isprime, x),true,false), numtheory:-sum2sqr(p)):
%p A226539 for n from 2 to 10^6 do
%p A226539   if nops(Prime2PairsSum(n)) = 2 then print(n, Prime2PairsSum(n)) fi;
%p A226539 od;
%t A226539 Select[Range@10000, Length[Select[ PowersRepresentations[#, 2, 2], And @@ PrimeQ[#] &]] == 2 &] (* _Giovanni Resta_, Jun 11 2013 *)
%o A226539 (PARI) select( is_A226539(n)={#[0|t<-sum2sqr(n),isprime(t[1])&&isprime(t[2])]==2}, [1..10^4]) \\ For more efficiency, apply selection to A045636. See A133388 for sum2sqr(). - _M. F. Hasler_, Dec 12 2019
%Y A226539 Cf. A054735 (restricted to twin primes), A037073, A069496.
%Y A226539 Cf. A045636 (sum of two squared primes: a superset).
%Y A226539 Cf. A214511 (least number having n representations).
%Y A226539 Cf. A226562 (restricted to sums decomposed in exactly three ways).
%K A226539 nonn
%O A226539 1,1
%A A226539 _Henk Koppelaar_, Jun 10 2013
%E A226539 a(25)-a(44) from _Giovanni Resta_, Jun 11 2013