Number of (n+1)X(3+1) 0..1 arrays x(i,j) with row sums sum{j*x(i,j), j=1..3+1} nondecreasing, and column sums sum{i*x(i,j), i=1..n+1} nondecreasing.

A232827

Number of (n+1)X(3+1) 0..1 arrays x(i,j) with row sums sum{j*x(i,j), j=1..3+1} nondecreasing, and column sums sum{i*x(i,j), i=1..n+1} nondecreasing.

Terms

    a(0) =23a(1) =128a(2) =578a(3) =2329a(4) =8898a(5) =32279a(6) =111609a(7) =367415a(8) =1156446a(9) =3507097a(10) =10298283a(11) =29408921a(12) =81999117a(13) =223720287a(14) =598317070a(15) =1572579642a(16) =4069639443a(17) =10383180004a(18) =26154898488a(19) =65117553622

External references