Table 1. Original grammar.

Start production
START	→	[INST]	start symbol
Basic productions
INST	→	ATOMIC	atomic production
INST	→	INST,INST	concatenation
INST	→	REP[INST]n	repeat family with n ∈ [2, 8]
REP	→	REP0	simple repeat
REP	→	REP1<ATOMIC>	repeat with starting point variation using ATOMIC
REP	→	REP2<ATOMIC>	repeat with resulting sequence variation using ATOMIC
Atomic productions
ATOMIC	→	-1	next element anticlockwise (ACW)
ATOMIC	→	-2	second element ACW
ATOMIC	→	-3	third element ACW
ATOMIC	→	+0	stays at same location
ATOMIC	→	+1	next element clockwise (CW)
ATOMIC	→	+2	second element CW
ATOMIC	→	+3	third element CW
ATOMIC	→	A	symmetry around one diagonal axis
ATOMIC	→	B	symmetry around the other diagonal axis
ATOMIC	→	H	horizontal symmetry
ATOMIC	→	V	vertical symmetry
ATOMIC	→	P	rotational symmetry