Irregular triangular array T read by rows: T(i,0 ) = T(i,2i) = 1 for i >= 0; T(i,1) = T(i,2i-1) = floor(i/2) for i >= 1; for even n >= 2, T(i,j) = T(i-1,j-2) + T(i-1,j-1) + T(i-1,j) for j = 2..2i-2, for odd n >= 3, T(i,j) = T(i-1,j-2) + T(i-1,j) for j = 2..2i-2.

A026536

Irregular triangular array T read by rows: T(i,0 ) = T(i,2i) = 1 for i >= 0; T(i,1) = T(i,2i-1) = floor(i/2) for i >= 1; for even n >= 2, T(i,j) = T(i-1,j-2) + T(i-1,j-1) + T(i-1,j) for j = 2..2i-2, for odd n >= 3, T(i,j) = T(i-1,j-2) + T(i-1,j) for j = 2..2i-2.

Terms

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

External references