a(n) = A171373(n+1) - 2*A171373(n).

Terms

a(0) =4a(1) =4a(2) =4a(3) =4a(4) =0a(5) =-12a(6) =-32a(7) =-52a(8) =-52a(9) =0a(10) =136a(11) =356a(12) =576a(13) =576a(14) =0a(15) =-1508a(16) =-3948a(17) =-6388a(18) =-6388a(19) =0a(20) =16724a(21) =43784a(22) =70844a(23) =70844a(24) =0a(25) =-185472a(26) =-485572a(27) =-785672a(28) =-785672a(29) =0