Perplexible

For these puzzles we need to fill in the cells with the numbers 1 through 5 so that each number appears exactly once in every row and column.  The clues here are all based around the average or mean of the numbers in adjacent cells.  A bottom heavy trapezoid indicates the mean is less than three, a top heavy one indicates it is greater than three, and a square indicates it is exactly three.  Some clues are deliberately left out in order to increase the difficulty in the later puzzles.

Here is a completed sample puzzle to provide a visual aid as to how these clues work:

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Posted in Puzzle by David Nacin, 05/13/20 7:01 PM
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Here’s a new Sudoku for the year 2020.  Instead of filling in cells with the numbers 1 through 9, we use the characters in “HAPPY2020”.  This means we have repeated P’s, 2’s and 0’s.  Inside each cage, arrows point from larger numbers to smaller ones and from letters later in the alphabet to earlier ones.  Arrows are placed whenever possible, so lack of an arrow between cells in the same cage also reveals important information.  For a demonstration on a single cage we have the following.

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Posted in Sudoku by David Nacin, 01/19/20 1:02 PM
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Fill in the diamonds with the numbers 1 through 5 so that each number appears exactly six times and no two adjacent diamonds contain the same number.  A white circle between diamonds indicates that the sum of the numbers in those diamonds is five.  A blue circle indicates the sum is six, and a grey circle indicates the sum is seven.

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Posted in Puzzle by David Nacin, 12/25/19 3:21 PM
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Here’s a letter puzzle I made for the holiday.  Place the letters of the word CANDY into the triangles so that each letter appears eight times and no two adjacent triangles share the same letter.  The clues tell you which of the letters comes first in the word CANDY but the color also matters.  White means the triangles on either side contain one consonant and one vowel.  Red means they either both contain consonants or both contain vowels.  For an example, here is one way out of many that a section of puzzle with these clues could be filled in:

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Posted in Puzzle by David Nacin, 12/11/19 11:40 PM
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Lots of Sudoku variants include some sort of extra clues based on the sizes of adjacent numbers.  In this puzzle arrows point from larger to smaller numbers in each three-by-three cage, but only when the larger number is exactly 1, 2, or 3 more than the smaller number.  Since arrows only appear when numbers are close, we can call this a Near Sizedoku.  Remember that arrows appear whenever possible, so lack of an arrow between adjacent cells in a cage also reveals some information.  For an example, this is one possibility for this three-by-three cage:

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Posted in Puzzle, Sudoku by David Nacin, 11/27/19 2:41 PM
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