Futoshiki· Advanced

Goal

Fill each row and column with numbers 1 to N without repeats

Rules

  • No duplicate numbers in any row
  • No duplicate numbers in any column
  • All inequality signs (< >) between adjacent cells must be satisfied
2
>
1
<
3
4

Follow inequality chains to narrow down possible values

Start with cells that have only one possible number

Adults aged 50+ who regularly solved number puzzles showed statistically significant improvements across all 14 cognitive measures including grammatical reasoning and spatial working memory. fNIRS studies also confirmed prefrontal cortex activation during constraint-based puzzles.

  • Number puzzles and 14 cognitive measures in adults 50+ (Int J Geriatr Psychiatry, 2019)
  • Prefrontal cortex activation during constraint puzzles via fNIRS (PMC, 2020)