I <3 SLEEPING

Challenge

We received this string, but I have no idea what it means!

1

3845281945283805284526053525260547380516453748164748478317454508

Hint: ARGH I CAN’T SLEEP PEOPLE KEEP STEALING MY ZZZZs . . . NO MORE ZZZs /cries

P.S. You’re overthinking it.

P.P.S. Blocks of 2

Final hint: sqrt(ABCDEFGHIJKLMNOPQRSTUVWXY). Where’d my Z’s go?

Solution

The “blocks of 2” hint combined with the hint that a letter is “missing”, leads us to suspect a Polybius cipher. Instead of comining I and J into a single letter, we simply omit the Z.
Also it seems like the first in each duo of letters is always 0-5, while the second is always 5-10, so this leads to the following Polybius square:

1
2
3
4
5
6

  0 1 2 3 4
5 a b c d e
6 f g h i j
7 k l m n o
8 p q r s t
9 u v w x y

Using this to translate we getegid

1
2
3
4

38 45 28 19 45 28 38 05 28 45 26 05 35 25 26 05 47 38 05 16 45 37 48 16 47 48 47 83 17 45 45 08
s  e  r  v  e  r  s  a  r  e  h  a  d  c  h  a  o  s  a  g  e  n  t  g  o  t  o  s  l  e  e  p

servers are had chaosagent go to sleep

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