If a, b in sequence, so is ab+7.

Terms

a(0) =2a(1) =11a(2) =29a(3) =65a(4) =128a(5) =137a(6) =263a(7) =281a(8) =326a(9) =533a(10) =569a(11) =659a(12) =722a(13) =848a(14) =1073a(15) =1145a(16) =1325a(17) =1415a(18) =1451a(19) =1514a(20) =1703a(21) =1892a(22) =2153a(23) =2297a(24) =2657a(25) =2837a(26) =2900a(27) =2909a(28) =3035a(29) =3098