# A very basic cipher

The following is a relatively basic cipher I have constructed. I still hope it's entertaining.

_ _ _ _ _ _ _
A _ A A A
A A _
A A
A D
B
B _
A A
B H


The answer is the 9-letter name of a famous man who helped created this puzzle.

Note the tag.

#### Medium hint:

Look at the name of puzzle, and remember that this involves math.

• I can change it then. I'm quite new to this exchange. Are the horizontal spaces useful? Oct 5 '21 at 19:34
• You mean the spaces between the underscores? I believe they are since the rest of the puzzle includes spaces between the letters. Also, if you ever want feedback before posting a puzzle, you can always join us in chat, or post your puzzle in the sandbox. Oct 5 '21 at 20:10
• Thank you. I was unaware of these things. Oct 5 '21 at 22:37

Initial thoughts:

Nine lines in the cipher, and nine letters to find, so likely one letter per line, so we are looking for a way to turn a row of multiple symbols into a single letter.
The tag combined with the low number of distinct symbols, and the latest letter being 'H' means we could be looking at a simple A=1, B=2 etc translation, with '_' representing 0.

Which gives us:

0000000
10111
110
11
14
2
20
11
28

But that doesn't obviously translate back to letters.

More thoughts:

The rapidly reducing line lengths, and nothing above N-1 in row N makes it look like we could have numbers in different bases. So try interpreting row N in base N.

Which gives us:

 0000000 (1) =  7 = G
10111 (2) = 23 = W
110 (3) = 12 = L
11 (4) =  5 = E
14 (5) =  9 = I
2 (6) =  2 = B
20 (7) = 14 = N
11 (8) =  9 = I
28 (9) = 26 = Z 

So the famous man we are looking for is:

Gottfried Wilhelm von Leibniz

As for the hints:

Now that I've solved it, I realise in that the second hint pointing to this "basic" cipher, and was providing a big signpost to the different bases, which I completely failed to spot...

• Congratulations on solving the cipher! : ) Leibniz is considered to be the inventor of the binary system as well as the first to show its use in a computing machine. Oct 8 '21 at 11:30