Differences between odd powers of 2 and the next smaller square.

Terms

a(0) =1a(1) =4a(2) =7a(3) =7a(4) =28a(5) =23a(6) =92a(7) =7a(8) =28a(9) =112a(10) =448a(11) =1792a(12) =7168a(13) =5503a(14) =22012a(15) =88048a(16) =166831a(17) =296599a(18) =444943a(19) =296863a(20) =1187452a(21) =4749808a(22) =7135951a(23) =4817239a(24) =19268956a(25) =77075824a(26) =118490767a(27) =94338007a(28) =377352028a(29) =1509408112