Number of n X n 0..4 matrices with each 2X2 subblock idempotent.
A224661
Number of n X n 0..4 matrices with each 2X2 subblock idempotent.
Terms
- a(0) =5a(1) =20a(2) =98a(3) =180a(4) =412a(5) =806a(6) =1606a(7) =3070a(8) =5808a(9) =10798a(10) =19866a(11) =36184
External references
- oeis: A224661