A bisection of A121649; a(n) = A121649(2*n+1) = A121648(2*n+1)^(1/2).

Terms

a(0) =1a(1) =2a(2) =5a(3) =16a(4) =51a(5) =170a(6) =564a(7) =1972a(8) =6847a(9) =24340a(10) =86071a(11) =309554a(12) =1108068a(13) =4003278a(14) =14415482a(15) =52545636a(16) =190858943a(17) =698449146a(18) =2548778173a(19) =9373091678a(20) =34371148421a(21) =126710479728a(22) =466022254144