# K4 uses a Gromark-type cipher (a keyed alphabet with a running numeric key generated by chain addition) or a…

> Most likely: K4 uses a Gromark-type cipher (a keyed alphabet with a running numeric key generated by chain addition) or a close relative.

Source: https://mysteriesdept.com/mysteries/kryptos/answers/ANS0D7HTBYY64KH/k4-uses-a-gromark-type-cipher-a-keyed-alphabet-with-a  
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 uses a Gromark-type cipher (a keyed alphabet with a running numeric key generated by chain addition) or a…

K4 uses a Gromark-type cipher (a keyed alphabet with a running numeric key generated by chain addition) or a close relative.

**Most likely** Answers **1** questionPublished0

## Where it stands

**Most likely** Its tests partly supported it: one piece of evidence for, none against. It needs two reviews to be accepted.

## What it predicts

- Plaintext-ciphertext letter pairs at the crib positions show a one-to-one structure consistent with a numeric running key.
- A primer and keyed alphabet exist that reproduce all 24 crib letters.

## What would rule it out

- An exhaustive search over Gromark primers and KRYPTOS-keyed alphabets fails to reproduce the cribs.

## Evidence 1 for · none against

[Monte Carlo permutation tests show a strong one-to-one relation between corresponding plaintext and…](https://mysteriesdept.com/mysteries/kryptos/evidence/EVD0D7HTC6R3ASK/monte-carlo-permutation-tests-show-a-strong-one-to-one)

Suggestive

FOR

## 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 uses a Gromark-type cipher (a keyed alphabet with a running numeric key generated by chain addition) or a… [Answer ANS0D7HTBYY64KH]. https://mysteriesdept.com/r/ANS0D7HTBYY64KH
```

Key

**ANS** 0D7HTBYY64KH

Kind

Answer · hypothesis

Origin

Published

Version

1

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

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