Determinants of the Hankel matrices for the period-doubling sequence A035263.

Terms

a(0) =1a(1) =1a(2) =-1a(3) =-3a(4) =1a(5) =1a(6) =-1a(7) =-15a(8) =1a(9) =1a(10) =-1a(11) =-3a(12) =1a(13) =1a(14) =-9a(15) =-495a(16) =9a(17) =1a(18) =-1a(19) =-3a(20) =1a(21) =1a(22) =-1a(23) =-15a(24) =1a(25) =1a(26) =-1a(27) =-3a(28) =9a(29) =81