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%I #23 Sep 08 2022 08:46:16
%S 3,17,71,107,881,1151,2591,3527,4049,15137,20807,34847,46817,69191,
%T 83231,103967,112337,139967,149057,176417,179999,206081,281249,362951,
%U 388961,438047,472391,478241,538721,649799,734471,808991,960497,1080449,1143071,1152161,1254527
%N Smaller member of a twin prime pair with a perfect power sum.
%C A069496 is a subsequence.
%H Amiram Eldar, <a href="/A270231/b270231.txt">Table of n, a(n) for n = 1..5000</a>
%e 3 is a term because 3 + 5 = 2^3.
%e 17 is a term because 17 + 19 = 6^2.
%e 107 is a term because 107 + 109 = 6^3.
%e 139967 is a term because 139967 + 139969 = 6^7.
%o (PARI) t(n,p=3) = { while( p+2 < (p=nextprime( p+1 )) || n-->0, ); p-2}
%o for(n=1, 1e4, if(ispower(2*t(n)+2), print1(t(n), ", ")));
%o (Magma) [p:p in PrimesUpTo(1300000)|IsPrime(p+2) and IsPower(2*p+2)]; // _Marius A. Burtea_, Dec 20 2019
%Y Cf. A001359, A069496, A330978, A330980.
%Y First bisection of A119768.
%K nonn
%O 1,1
%A _Altug Alkan_, Mar 13 2016
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