Matrix Multiplication in O(n²log₂6)

A11xB11 + A12xB21	A11xB12 + A12xB22
A21xB11 + A22xB21	A21xB12 + A22xB22

M1 = (A11+A21)x(B11-B12)
M2 = (A12+A22)x(B21-B22)
M3 = (A11+A21)x(B11+B12)
M4 = (A12+A22)x(B21+B22)
M5 = A11xB11
M6 = A12xB21

S1 = (M1+M3)/2
S2 = (M2+M4)/2
S3 = (M3-M1)/2
S4 = (M4-M2)/2
S5 = (M1+M2+M3+M4)/2
S6 = (M1-M2+M3-M4)/2

S1+S2 = C11+C21
S3+S4 = C12+C22
S5 = C11+C22
S6 = C12+C21
S7 = C1+C2+C3+C4

S8 = S5+S1+S2-S7=C11-C12
S9 = S7-S5-S1-S2=C12-C11
SA = S6+S3+S4-S7=C21-C22
SB = S7-S6-S3-S4=C22-C21

C11 = M5+M6
C12 = C11-S8
C21 = S1+S2-C11
C22 = S3+S4-C12