Number of (n+1)X(3+1) 0..3 arrays with no 2X2 subblock having the sum of its diagonal elements greater than the maximum of its antidiagonal elements.

A251023

Number of (n+1)X(3+1) 0..3 arrays with no 2X2 subblock having the sum of its diagonal elements greater than the maximum of its antidiagonal elements.

Terms

    a(0) =1966a(1) =8207a(2) =20608a(3) =51347a(4) =118871a(5) =272547a(6) =608267a(7) =1356939a(8) =3017800a(9) =6755296a(10) =15194024a(11) =34402203a(12) =78257659a(13) =178761713a(14) =409448316a(15) =939731942a(16) =2159479782a(17) =4966624315a(18) =11428488961a(19) =26305947749a(20) =60561558048a(21) =139440168208

External references