a(n)=A132658(n+1)-2*A132658(n).

Terms

a(0) =0a(1) =1a(2) =1a(3) =0a(4) =-1a(5) =-1a(6) =0a(7) =-21a(8) =-21a(9) =0a(10) =21a(11) =21a(12) =0a(13) =-903a(14) =-903a(15) =0a(16) =903a(17) =903a(18) =0a(19) =-38829a(20) =-38829a(21) =0a(22) =38829a(23) =38829a(24) =0a(25) =-1669647a(26) =-1669647a(27) =0a(28) =1669647a(29) =1669647