Eight white kings and one red king on a 3 X 3 chessboard. G.f.: (1 + 2*x - 4*x^2)/(1 - 2*x - 8*x^2).
A179607
Eight white kings and one red king on a 3 X 3 chessboard. G.f.: (1 + 2*x - 4*x^2)/(1 - 2*x - 8*x^2).
Terms
- a(0) =1a(1) =4a(2) =12a(3) =56a(4) =208a(5) =864a(6) =3392a(7) =13696a(8) =54528a(9) =218624a(10) =873472a(11) =3495936a(12) =13979648a(13) =55926784a(14) =223690752a(15) =894795776a(16) =3579117568a(17) =14316601344a(18) =57266143232a(19) =229065097216a(20) =916259340288
External references
- oeis: A179607