# MAPLE. June 4, 2006. # # Supports of weight 6 vectors in extended ternary Golay code. # These form a 5-(12,6,1) design. d := 4; v := [1 , 45 , 40 , 45 , 1]; verts := 132; Q := matrix([ [1 , 11 , 54 , 55 , 11 ], [1 , 11/3 , 6/5 , -11/3 , -11/5], [1 , 0 , -27/5 , 0 , 22/5 ], [1 , -11/3 , 6/5 , 11/3 , -11/5], [1 , -11 , 54 , -55 , 11 ] ]); # Tridiagonal matrix L = L1-star can be used to obtain Q (and # then all parameters) from just the cosines. L := matrix([ [0 , 11 , 0 , 0 , 0 ], [1 , 0 , 10 , 0 , 0 ], [0 , 55/27, 0 , 242/27 , 0 ], [0 , 0 , 44/5, 0 , 11/5], [0 , 0 , 0 , 11 , 0 ] ]); [0 45 0 0 0] [ ] [1 20 16 8 0] [ ] L_1 = [0 18 9 18 0] [ ] [0 8 16 20 1] [ ] [0 0 0 45 0] [0 0 40 0 0] [ ] [0 16 8 16 0] [ ] L_2 = [1 9 20 9 1] [ ] [0 16 8 16 0] [ ] [0 0 40 0 0] [0 0 0 45 0] [ ] [0 8 16 20 1] [ ] L_3 = [0 18 9 18 0] [ ] [1 20 16 8 0] [ ] [0 45 0 0 0] [0 0 0 0 1] [ ] [0 0 0 1 0] [ ] L_4 = [0 0 1 0 0] [ ] [0 1 0 0 0] [ ] [1 0 0 0 0] [1 45 40 45 1] [ ] [1 15 0 -15 -1] [ ] P = [1 1 -4 1 1] [ ] [1 -3 0 3 -1] [ ] [1 -9 16 -9 1] [1 11 54 55 11 ] [ ] [1 11/3 6/5 -11/3 -11/5] [ ] Q=[1 0 -27/5 0 22/5 ] [ ] [1 -11/3 6/5 11/3 -11/5] [ ] [1 -11 54 -55 11 ] [0 11 0 0 0 ] [ ] [1 0 10 0 0 ] [ ] [ 55 242 ] Ls1 = [0 -- 0 --- 0 ] [ 27 27 ] [ ] [0 0 44/5 0 11/5] [ ] [0 0 0 11 0 ] [0 0 54 0 0 ] [ ] [0 10 0 44 0 ] [ ] [ 1083 242] [1 0 ---- 0 ---] Ls2 = [ 25 25 ] [ ] [0 44/5 0 226/5 0 ] [ ] [ 1188 162] [0 0 ---- 0 ---] [ 25 25 ] [0 0 0 55 0 ] [ ] [0 0 44 0 11 ] [ ] [ 242 1243 ] Ls3 = [0 --- 0 ---- 0 ] [ 27 27 ] [ ] [1 0 226/5 0 44/5] [ ] [0 11 0 44 0 ] [0 0 0 0 11] [ ] [0 0 0 11 0 ] [ ] [ 242 33] [0 0 --- 0 --] Ls4 = [ 25 25] [ ] [0 11/5 0 44/5 0 ] [ ] [ 162 88] [1 0 --- 0 --] [ 25 25]