Exercise 7.17

• Digit ’2’ will have ${\varphi }_1,{\varphi }_3$
• Digit ’3’ will have ${\varphi }_1,{\varphi }_6$
• Digit ’4’ will have ${\varphi }_2$
• Digit ’6’ will have ${\varphi }_3$
• Digit ’7’ will have ${\varphi }_2$
• Digit ’8’ will have ${\varphi }_3,{\varphi }_6$
• Digit ’9’ will have ${\varphi }_1,{\varphi }_2$

The additional basic shapes shall be able to be composed together to construct each digit. They shouldn’t be too big and should not overlap with each other.