a(n) = smallest k such that k*2^n - 7 is a square.

Terms

a(0) =7a(1) =4a(2) =2a(3) =1a(4) =1a(5) =1a(6) =2a(7) =1a(8) =11a(9) =11a(10) =32a(11) =16a(12) =8a(13) =4a(14) =2a(15) =1a(16) =4006a(17) =2003a(18) =9284a(19) =4642a(20) =2321a(21) =107566a(22) =53783a(23) =313702a(24) =156851a(25) =1364479a(26) =1493338a(27) =746669a(28) =12145148a(29) =6072574