Solve 2^n - 2 = 7(x^2 - x) + (y^2 - y) for (x,y) with x>0, y>0; sequence gives value of x.

Terms

a(0) =1a(1) =1a(2) =1a(3) =2a(4) =1a(5) =3a(6) =4a(7) =2a(8) =9a(9) =6a(10) =12a(11) =23a(12) =1a(13) =46a(14) =45a(15) =47a(16) =136a(17) =43a(18) =229a(19) =314a(20) =144a(21) =771a(22) =484a(23) =1058a(24) =2025a(25) =91a(26) =4140a(27) =3959a(28) =4321a(29) =12238