Diagonal sums of number triangle A117901.

Terms

a(0) =1a(1) =-1a(2) =1a(3) =-2a(4) =4a(5) =-2a(6) =-5a(7) =14a(8) =-5a(9) =-26a(10) =64a(11) =-26a(12) =-101a(13) =254a(14) =-101a(15) =-410a(16) =1024a(17) =-410a(18) =-1637a(19) =4094a(20) =-1637a(21) =-6554a(22) =16384a(23) =-6554a(24) =-26213a(25) =65534a(26) =-26213a(27) =-104858a(28) =262144a(29) =-104858