Hypotenuses of primitive Pythagorean triples in A195556 and A195557.

Terms

a(0) =1a(1) =13a(2) =25a(3) =37a(4) =493a(5) =949a(6) =1405a(7) =18721a(8) =36037a(9) =53353a(10) =710905a(11) =1368457a(12) =2026009a(13) =26995669a(14) =51965329a(15) =76934989a(16) =1025124517a(17) =1973314045a(18) =2921503573a(19) =38927735977a(20) =74933968381a(21) =110940200785