Challenge Level

This solution comes from Chris. Well
done!

22 | 20 | 18 | 16 | 14 |

26 | 24 | 22 | 20 | 18 |

30 | 28 | 26 | 24 | 22 |

34 | 32 | 30 | 28 | 26 |

38 | 36 | 34 | 32 | 30 |

The diagonal is the same as +2, because it's the same as + 4
then - 2.

2 | 6 | 18 | 54 | 162 |

4 | 12 | 36 | 108 | 324 |

8 | 24 | 72 | 216 | 648 |

16 | 48 | 144 | 432 | 1296 |

32 | 96 | 288 | 864 | 2592 |

The diagonal is the same as x 6, because it's x 2 and then x
3.

The diagonal is the same as halving the width and doubling the height at the same time.