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4 votes

Checkmate N Kings with M Knights Perfectly

If I'm not missing something these are
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2 votes

Checkmate N Kings with M Knights Perfectly

The answer I got is : The position(s): Position number 1: Position number 2:
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  • 1,042
4 votes

Checkmate N Kings with M Knights Perfectly

I'll stand by my initial comment: All kings should be attacked by at least two knights. If any king is attacked by only one knight, the attacking knight must not be threatened by another king. This ...
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1 vote

Checkmate N Kings with M Knights

The answer I found is: Explanation:
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  • 1,042
-1 votes

A 16 Clue Sudoku Puzzle (but the kings can't be in check)

I've just solved it. Solution as gif:
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10 votes

Reconstructing the Candidates Tournament 2018

I am assuming the shared nationalities rule means that the Karjakin-Kramnik, Kramnik-Grischuk, and Karjakin-Grischuk games occurred in rounds 1, 2, and 3, but that the one Russian player not involved ...
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  • 101
20 votes
Accepted

Checkmate N Kings with M Knights

50 Kings,14 Knights: This is optimal but not unique, see bottom of this answer. Reasoning: I think the problem is equivalent to covering every square on the board with as few knights as possible and ...
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10 votes

Checkmate N Kings with M Knights

This seems like it could be optimal [Edit: it is not - see loopy walt's answer]: 16 knights, and 48 kings.
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8 votes
Accepted

Symmetrical Chess Position With No Legal Moves

All a matter of getting your pins right:
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3 votes

The Pawn March Problem

A simple fact: The reachable rank is unbounded. Proof: An asymptotic bound: The reachable rank is O(sqrt n log n) Proof (sketch): It seems there is still room for improvement here, cf. last sentence ...
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1 vote

The Pawn March Problem

Here is an upper bound. Here is how This strategy is not optimal though.
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3 votes

The Rook's Hassle

I was wrong, it is doable. Solution, without spoilers. It is easy enough to see that there are 4 black pawns under white ones. Therefore, there had to be 4 captures. White is missing a pawn, black is ...
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  • 1,695
14 votes

Checkmate 30 kings with rooks

This just gives a lower bound on what the best solution could be. For a black king to be in mate, all neighboring fields must be either threatened or blocked and the field where the king is must be ...
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  • 419
30 votes
Accepted

Checkmate 30 kings with rooks

Here's a solution with 11 rooks and 1 king: kkkRkkRk/2kRkkRk/R1kkkkkk/2k2Rk1/k1k1R1k1/k4Rk1/kRkk3R/kR1kkk1K b - - 0 1 https://lichess.org/editor/kkkRkkRk/2kRkkRk/R1kkkkkk/2k2Rk1/k1k1R1k1/k4Rk1/kRkk3R/...
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  • 8,004
4 votes

Checkmate 30 kings with rooks

Another solution with 12 rooks and 3 kings: FEN: k1RR1k1K/kkkkkk2/RRkkRRk1/kkkkkk2/k1RRk2K/kkkkk1K1/RRkkR3/kkk1Rk2 w - - 0 1
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12 votes

Checkmate 30 kings with rooks

Solution with 12 rooks and 3 kings: https://lichess.org/editor/K1k2Rkk/2kkkRk1/1kRRkkk1/2kkkkRR/K1kkRkk1/3kRkkk/1KRk1kRk/1R1kkkRk_w_-_-_0_1 There are some trivial modifications to add 2 checkmated ...
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  • 1,695
5 votes

Checkmate 30 kings with rooks

Here is a solution with 1 king, 13 rooks. It feels like it might be possible to remove one rook with a few adjustments, but I haven't achieved this after hours of shuffling pieces around. For a ...
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  • 5,088
15 votes

Checkmate 30 kings with rooks

To kick things off, here is a solution with 1 white king and 14 white rooks. I have a feeling this could be tweaked to remove a rook by adding some more kings, but haven't quite managed yet.
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3 votes

The Rook's Hassle

I don't have a complete answer, but I figured I'd post a partial answer here in case someone else feels motivated to continue where I left off. This is one of the most challenging and fun problems I'...
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