Number of 3Xn 0..1 arrays with row sums nondecreasing and column sums unimodal.
A223627
Number of 3Xn 0..1 arrays with row sums nondecreasing and column sums unimodal.
Terms
- a(0) =4a(1) =26a(2) =147a(3) =751a(4) =3560a(5) =15778a(6) =67030a(7) =274631a(8) =1088767a(9) =4218662a(10) =16015929a(11) =59653826a(12) =219063215a(13) =794078382a(14) =2843032061a(15) =10081383128a(16) =35429305737a(17) =123436612116a(18) =427070556002
External references
- oeis: A223627