Detects empty corner squares (a1, h1, a8, h8) that are not attacked by either side.
SAE concept sae_1742 fires when detects empty corner squares (a1, h1, a8, h8) that are not attacked by either side.. It appears in 19 of 9,950 Climbchess puzzles (0.2%), spanning ELO 618–2655 (median 1169).
Free forever · no email · no signup · delete data anytime.
This page documents Detects empty corner squares (a1, h1, a8, h8)…, one of 4,505 interpretable chess concepts extracted from Leela Chess Zero via sparse autoencoders. The full feature description from our SAE labelling pipeline reads:
Detects empty corner squares (a1, h1, a8, h8) that are not attacked by either side.
This pattern fires in 19 of our 9,950 tagged puzzles. The puzzles where it appears span ELO 618 to 2655, with a median rating of 1169. That distribution tells you whether this is a beginner cue or a master-level subtlety.
Pattern statistics
| Concept ID | sae_1742 |
|---|---|
| Puzzles where it fires | 19 |
| Min ELO | 618 |
| Median ELO | 1169 |
| Max ELO | 2655 |
| Coverage | 0.19% of puzzle set |
Related concepts
The five concepts most often co-firing alongside this one (Jaccard similarity over the puzzle co-occurrence graph) are:
Example puzzles
Below are 10 puzzles spanning the rating distribution. Each links to its own page with full move list and related concepts.
- Puzzle yZzjp — ELO 618, themes: arabianMate, endgame, mate, side to move: White
- Puzzle yZzjp_F — ELO 618, themes: arabianMate, endgame, mate, side to move: Black
- Puzzle zmRyc — ELO 866, themes: endgame, hookMate, mate, side to move: Black
- Puzzle zJGoD — ELO 1111, themes: advancedPawn, crushing, endgame, side to move: White
- Puzzle zJGoD_M — ELO 1111, themes: advancedPawn, crushing, endgame, side to move: White
- Puzzle zzxLf_F — ELO 1169, themes: endgame, mate, mateIn2, side to move: White
- Puzzle x568R — ELO 1456, themes: endgame, hookMate, master, side to move: Black
- Puzzle np7Af — ELO 1947, themes: arabianMate, endgame, mate, side to move: Black
- Puzzle iT2eB_M — ELO 2012, themes: arabianMate, endgame, exposedKing, side to move: Black
- Puzzle zWdty_F — ELO 2655, themes: endgame, long, mate, side to move: Black
How to use this page
If you want to train this pattern, open the Climbchess trainer and filter for puzzles tagged with this concept. The trainer surfaces them at the right difficulty for your current rating, and tracks how often you spot the cue versus miss it. You can also browse the related concepts above to see neighbouring ideas in feature space.
Climbchess concepts are not heuristics written by a human author. Each one corresponds to a single direction in the residual stream of Leela Chess Zero that activates on a specific board feature, then was labelled by reading the top-activating positions. This makes the catalogue exhaustive (every Leela-detectable pattern is in here somewhere) and falsifiable (you can replay our extraction).
Frequently asked
What is SAE concept sae_1742?
Detects empty corner squares (a1, h1, a8, h8) that are not attacked by either side. It is one of 4,505 interpretable features extracted from Leela Chess Zero's residual stream via sparse autoencoders, then labelled by reading the top-activating positions.
Where does this pattern appear?
In 19 tagged puzzles (0.2% of the set), spanning Lichess ELO 618 to 2655 with a median of 1169.
How do I train it?
Open the Climbchess trainer and filter for puzzles tagged with this concept. The trainer adapts difficulty using your live recognition profile and tracks how often you spot the cue versus miss it.
Is it free?
Yes. Climbchess is free forever, with no account, email, or signup required. You can delete your data at any time.