Number of solutions to 1 +-*/ 2 +-*/ 3 +-*/ ... +-*/ n = 0.

Terms

a(0) =0a(1) =0a(2) =1a(3) =1a(4) =1a(5) =5a(6) =8a(7) =18a(8) =39a(9) =91a(10) =185a(11) =460a(12) =1051a(13) =2526a(14) =6280a(15) =15645a(16) =35516a(17) =93765a(18) =225989a(19) =611503