Column 4 of array in A265080.

Terms

a(0) =0a(1) =4a(2) =20a(3) =108a(4) =544a(5) =2540a(6) =11544a(7) =52192a(8) =231872a(9) =1014444a(10) =4401400a(11) =19016888a(12) =81588720a(13) =347833408a(14) =1476460496a(15) =6250982640a(16) =26366866432a(17) =110825294252a(18) =464575219704