# K4 is a Hill (matrix) cipher, hinted at by the extra L that spells HILL down the tableau's last column.

> Disputed: K4 is a Hill (matrix) cipher, hinted at by the extra L that spells HILL down the tableau's last column.

Source: https://mysteriesdept.com/mysteries/kryptos/answers/ANS0D7HTCEJ6D8G/k4-is-a-hill-matrix-cipher-hinted-at-by-the-extra-l-that  
Publisher: Mysteries Department  
Licence: CC BY 4.0 (credit Mysteries Department and link the page)  

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[Questions](https://mysteriesdept.com/questions)[Kryptos](https://mysteriesdept.com/mysteries/kryptos)[What kind of cipher is K4?](https://mysteriesdept.com/mysteries/kryptos/questions/QST0D7HT81Y2GZY/what-kind-of-cipher-is-k4)Answer

Answer · Kryptos

# K4 is a Hill (matrix) cipher, hinted at by the extra L that spells HILL down the tableau's last column.

K4 is a Hill (matrix) cipher, hinted at by the extra L that spells HILL down the tableau's last column.

**Disputed** Answers **1** questionPublished0

## Where it stands

**Disputed** One piece of evidence for, one against. It needs two reviews to be accepted.

## What it predicts

- Some invertible matrix over the alphabet maps the crib blocks to their ciphertext.

## What would rule it out

- No matrix of plausible size is consistent with the cribs.

## Evidence 1 for · 1 against

[With the extra L, the letters H I L L run down the tableau's right-hand column.](https://mysteriesdept.com/mysteries/kryptos/evidence/EVD0D7HTCPC468E/with-the-extra-l-the-letters-h-i-l-l-run-down-the-tableaus)

Speculative

FOR

[Bauer, Link and Molle tested the matrix conjecture; it has not produced a solution.](https://mysteriesdept.com/mysteries/kryptos/evidence/EVD0D7HTCY62JZ9/bauer-link-and-molle-tested-the-matrix-conjecture-it-has-not)

Suggestive

AGAINST

## The questions it answers

[What kind of cipher is K4?](https://mysteriesdept.com/mysteries/kryptos/questions/QST0D7HT81Y2GZY/what-kind-of-cipher-is-k4)

Most likelyK4 uses a Gromark-type cipher (a keyed alphabet with a running numeric key generated by chain addition) or a…

## Cite it

```
Mysteries Department. (2026). K4 is a Hill (matrix) cipher, hinted at by the extra L that spells HILL down the tableau's last column. [Answer ANS0D7HTCEJ6D8G]. https://mysteriesdept.com/r/ANS0D7HTCEJ6D8G
```

Key

**ANS** 0D7HTCEJ6D8G

Kind

Answer · hypothesis

Origin

Published

Version

1

Added by

[apollo](https://mysteriesdept.com/u/apollo)

The record

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