### Random Post

### Recent Posts

### Recent Comments

Jim Randell on Enigma 1691: Factory part… | |

Jim Randell on Puzzle 52: Football on the Isl… | |

geoffrounce on Enigma 1691: Factory part… | |

Hugh Casement on Enigma 1070: Time to work | |

Jim Randell on Enigma 1070: Time to work |

### Archives

### Categories

- article (11)
- enigma (1,157)
- misc (2)
- project euler (2)
- puzzle (40)
- site news (44)
- tantalizer (42)
- teaser (3)

### Site Stats

- 177,808 hits

Advertisements

The following Python program runs in 38ms.

In order to get a solution I have to assume a 3-segment “7” (rather than the 4-segment “7” that my old Casio calculator actually displays). Choosing 5-segment “6” and “9” digits (rather than the more usual 6-segment display) does not affect the solution.

Solution:The number illuminates 41 segments of the display.I was puzzled as to why I wasn’t getting any solution with a 4-segment 7.

I get the same result: one solution with a 3-segment 7, no solution with 4-segment 7.

Now I have my paper copy of the magazine there is a diagram showing the digits, and it makes clear that a 3-segment “7” is used (and 6-segment “6” and “9”). I have updated the question to the show the arrangement of the digits.

Ah, that explains it. I was wondering whether the original specified the display.

Looking at numbers with fewer than ten digits I found

130691232 = 42^5

1336336 = 34^4, 1500625 = 35^4, 2560000 = 40^4.

These don’t depend on a three-segment 7 (normal for clocks but not calculators, for reasons that are lost on me). I’ve never heard them called “illuminated strips”!

Here is mine: