a(1)=3; for n > 1, a(n) = 1 + a(n-1) + gcd( a(n-1)*(a(n-1)+2), A073829(a(n-1)) ).

Terms

a(0) =3a(1) =19a(2) =39a(3) =81a(4) =165a(5) =333a(6) =335a(7) =673a(8) =1347a(9) =1349a(10) =1351a(11) =1353a(12) =1355a(13) =1357a(14) =1359a(15) =2721a(16) =2723a(17) =2725a(18) =2727a(19) =5457a(20) =5459a(21) =5461a(22) =5463a(23) =5465a(24) =5467a(25) =5469a(26) =10941a(27) =10943a(28) =10945a(29) =10947