Largest prime factor of 2^(2*n+1)+2^(n+1)+1.

Terms

a(0) =13a(1) =41a(2) =29a(3) =109a(4) =2113a(5) =157a(6) =1321a(7) =26317a(8) =525313a(9) =1429a(10) =1657a(11) =268501a(12) =279073a(13) =536903681a(14) =49477a(15) =4327489a(16) =7416361a(17) =231769777a(18) =21841a(19) =43249589a(20) =500177a(21) =29247661a(22) =7484047069a(23) =19707683773a(24) =1326700741a(25) =586477649a(27) =275415303169a(28) =104399276341