Pencil logic puzzles

Do you know Sudoku? Or maybe Paint by Numbers (also known as Nonogram)? Sudoku and Nonogram are examples of the many kinds of puzzles also known as "pencil logic puzzles" (for the lack of better terms).

Pencil logic puzzles are puzzles that usually have a grid (so you usually don't need to spare some space just to start solving), and which are typically intended to be filled with pencil or pen (and thus shouldn't be interactive). Moreover, as a logic puzzle, it should have a unique solution, reachable by (deductive) logic alone, and most often these puzzles are culture-neutral in the sense that you don't have to understand any particular culture (except possibly basic math) to solve the puzzles. This rules out things such as knights and knaves (for not having a grid and is also rather culture-heavy), logic grid puzzles (for being culture-heavy), puzzlehunt puzzles (for not being deductive), or puzzle video games (for not being doable with pencil).

So, what are examples of pencil logic puzzles? Sudoku and Nonogram are examples of them, but you might have seen examples such as Battleships, Slitherlink, or maybe recently Fillomino.

There are generally two major types of people indulging in such puzzles. The first one is publishers of these and casual consumers of such; if you've seen Sudoku books in stores, most likely they are made by these publishers. Puzzles in this kind are almost exclusively Sudoku (as the most popular sort), and mostly computer-generated. They sell pretty good, but they are usually of lower quality; after all, computers can generate plenty of puzzles, but can't determine whether they are aesthetically good and stuff.

The second one, which I belong in, is one that enjoys high-quality puzzles, those that are carefully hand-crafted. There aren't so many of us, but if you're looking, you can find a heck lot of them (with apologies to people that I can't think up their blogs fast enough). In fact, there is even a federation complete with its own puzzle and sudoku championships. (Naturally, they are about solving puzzles as fast as possible.)

Now, are you interested in exploring the world of high-class puzzles?

I have collected such puzzles I found in my set here. Feel free to comment here or notify me somehow if you want an inclusion. To be in this set, the puzzle must be a pencil logic puzzle, following the above rules. To be more succinct, puzzles in this set must be:

Pencil (can be solved on paper, so not interactive; no Sokoban)
Deductive (can be solved with deduction, no need of inductive logic; no puzzlehunt-style puzzles)
Culture-neutral (can be solved without knowing any particular culture, except basic math; no crossword, no elimination grid, no knights and knaves)

Markdown

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**bold** or __bold__

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1. numbered
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numbered
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paragraph 1

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paragraph 1

paragraph 2

[example link](https://brilliant.org)

example link

> This is a quote

This is a quote

    # I indented these lines
    # 4 spaces, and now they show
    # up as a code block.

    print "hello world"

# I indented these lines
# 4 spaces, and now they show
# up as a code block.

print "hello world"

Math

Appears as

Remember to wrap math in $ ... $ or \[ ... \] to ensure proper formatting.

2 \times 3

2 \times 3

2^{34}

2^{34}

a_{i-1}

a_{i-1}

\frac{2}{3}

\frac{2}{3}

\sqrt{2}

\sqrt{2}

\sum_{i=1}^3

\sum_{i=1}^3

\sin \theta

\sin \theta

\boxed{123}

\boxed{123}

Easy Math Editor

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Markdown	Appears as
`italics` or `_italics_`	italics
`bold` or `__bold__`	bold
- bulleted - list	bulleted list
1. numbered 2. list	numbered list
Note: you must add a full line of space before and after lists for them to show up correctly
paragraph 1 paragraph 2	paragraph 1 paragraph 2
`[example link](https://brilliant.org)`	example link
`> This is a quote`	This is a quote
# I indented these lines # 4 spaces, and now they show # up as a code block. print "hello world"	# I indented these lines # 4 spaces, and now they show # up as a code block. print "hello world"

Math	Appears as
Remember to wrap math in `$` ... `$` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$

Comments

Do you hear the Sudoku Wiki Page calling out for you? It feels so lonely right now.

Calvin Lin Staff - 6 years, 1 month ago

Surprisingly, I am less versed in Sudoku than in other puzzles (my favorite kinds of the type are Fillomino and Heteromino at the moment). Perhaps one of the reasons is that it is so saturated with so many tricks that normal Sudoku is mostly "look for the correct trick and apply it". If I have some ideas on what to write about Sudoku, I'll write it up.

Ivan Koswara - 6 years, 1 month ago

Well Yeah! I have always solved many like Battleship, Slitherlink and Sudoku.

I didn't know that there is a federation! And man, Ulrich Voigt! He has won the Championship 7 times. God Knows what his Speed would be. I am Now Way too interested in Solving more of these! :D Thanks For Sharing, Mate!

Mehul Arora - 6 years, 1 month ago

Hi Ivan !

I have always been interested in those things in which we have to challenge ourselves . Just like Sudoku , Rubik's cube , the 15 puzzle , Brainvita , Tangram and related stuffs..

I just feel a surge of energy flow through me when I attempt such things .

How about you ?

A Former Brilliant Member - 6 years, 1 month ago

I find a surge of energy flow through me when I'm doing some competitive puzzle solving, for obvious reasons. During casual solving I just find it pleasant, no rush or anything of the sort. (It also allows me to find and appreciate good puzzles.)

Yeah! Pumped up and already solved battleship, Sudoku, and rubik's cube

Steve Chen - 6 years, 1 month ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$