It is the 90 degree corner of the triangle which acts as the point of the arrow (rather than either of the two 45 degree corners). Does this help?

In Max/Min Triplet Sums, I have identified the outside clue-whether max or min- but I am unable to figure out how to use this information as help in solving the Sudoku (apart from Classic rules) ? Please help..

Not able to figure out the two digits which is pointed by corresponding arrowhead.

Vishal,

Re: Max/Min Triplet Sums

I'm not very good at walkthroughs.

Try the following. Place two missing 8s by standard logic. Place 2s in boxes 6 and 7 by standard logic. Place 3 in box 8 by standard logic. Place 1 in box 3 by standard logic.

Now in row 4, the missing 1 cannot sit either side of the 3 and 2 (otherwise we would have a 6 sum in that row and we are told that 10 is the minimum sum) so it must go in column 2.

In the same row, the missing 5 must be either side of the 3 and 2 (otherwise we can't have a 10 sum). Therefore, column 3 in that row must have a 6.

In column 5, the 8 sum must be 1-3-4 in some order as the 2 is isolated. The 1 can't lie below the 3 as there would then be a 6 sum. So the 1 must go in row 5 and the 4 in row 6.

In box 4, the missing 3 can't go in bottom right corner as there would then be a 9 sum in row 6. So it goes immediately above that with the missing 4 to its left.

Then look at the 8 sum in column 3. etc.

Edited by David McNeill 2016-02-19 8:36 PM

Mihiryadav,

Re: Arrowhead

Consider the diagonally split cell in top right corner of box 5. The arrow cannot point to the south-east as the first digit in that direction is a 9 and the sum of the first two digits will therefore exceed the allowed value. So, the arrow must point to the north-west and the first two digits in this direction are 3 and 4, adding to 7. The top left triangle in our split cell is coloured black and a 7 is placed in the bottom right triangle.

Hope this gets you going.

How well did you like the theme of the contest?	I really liked the theme
What was your opinion of the distribution of easy/hard puzzles?	Too many hard puzzles
What did you think about the puzzle quality of the test?	Very nice
Your 3 most favorite puzzles of the contest.	12. Renban Squeeze
Your 3 most favorite puzzles of the contest.	10. Tight Fit
Your 3 most favorite puzzles of the contest.	11. Non-Consecutive Squeeze

How well did you like the theme of the contest?	I somewhat liked the theme
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Very nice
Your 3 most favorite puzzles of the contest.	7. Max/Min Triplet Sums
Your 3 most favorite puzzles of the contest.	13. Triangular Sums
Your 3 most favorite puzzles of the contest.	4. Trio

This was a good test :) would have given it 3-stars if online solving was available - I don't have a printer so for puzzles without online solving I have to write all my answers in MSPaint with my mouse, which makes it take quite a bit longer and makes it difficult to write pencil marks.

Thanks David for your help and guiding me through the solving technique.. By the way, I failed to understand the rule - it was for all the combinations of consecutive numbers along a row and column; not only for the first 3...Thanks for your explanation..

How well did you like the theme of the contest?	I really liked the theme
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Very nice
Your 3 most favorite puzzles of the contest.	6. Outside Sums
Your 3 most favorite puzzles of the contest.	7. Max/Min Triplet Sums
Your 3 most favorite puzzles of the contest.	12. Renban Squeeze

How well did you like the theme of the contest?	I somewhat liked the theme
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Fairly Nice
Your 3 most favorite puzzles of the contest.	9. Thropki
Your 3 most favorite puzzles of the contest.	14. Arrowhead
Your 3 most favorite puzzles of the contest.	10. Tight Fit

How well did you like the theme of the contest?	I somewhat liked the theme
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Very nice
Your 3 most favorite puzzles of the contest.	6. Outside Sums
Your 3 most favorite puzzles of the contest.	13. Triangular Sums
Your 3 most favorite puzzles of the contest.	9. Thropki

I really liked this test.Normally,I hate Math based variants in sudoku but this test was different.I remember thinking before the test that I would be happy with a score somewhere around 400.I didn't expect 470 in 90 mins(74?!).In the last 16 mins of the test,I really had a go at Thropki(100) but it seemed beyond my reach despite multiple guesses.

I greatly enjoyed solving Outside and Triangular sums both of which had a very systematic solve and I also loved the squeeze variants.

Thanks a lot to David for this wonderful test and to all test solvers. The set was delightful and I had great fun!

I have two questions on triangular sums:
1. Are we sure that we won't split any more cells? I am confused because the rule says triangles cannot touch grid boundary. These already placed ones are far enough not to touch :)
2. May the three numbers around a triangle be same?

Bskbri,

Re: Triangular Sums

All split cells will be indicated before solving.

There is no special rule prohibiting more than one edge of a triangle having the same digit.

How well did you like the theme of the contest?	I really liked the theme
What was your opinion of the distribution of easy/hard puzzles?	Too many hard puzzles
What did you think about the puzzle quality of the test?	Very nice
Your 3 most favorite puzzles of the contest.	10. Tight Fit
Your 3 most favorite puzzles of the contest.	3. Classic
Your 3 most favorite puzzles of the contest.	6. Outside Sums

How well did you like the theme of the contest?	I somewhat liked the theme
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Very nice
Your 3 most favorite puzzles of the contest.	14. Arrowhead
Your 3 most favorite puzzles of the contest.	8. Thropki
Your 3 most favorite puzzles of the contest.	9. Thropki

I am unable to submit Classic-3 solution. The answer key is A - 249516837 and B - 847925316

Sorry, was typing the wrong answer I guess. The key was not allowing me to submit.

Edited by aashay 2016-02-20 10:27 PM

How well did you like the theme of the contest?	I really liked the theme
What was your opinion of the distribution of easy/hard puzzles?	Too many hard puzzles
What did you think about the puzzle quality of the test?	Very nice
Your 3 most favorite puzzles of the contest.	5. Anti-Diagonal
Your 3 most favorite puzzles of the contest.	6. Outside Sums
Your 3 most favorite puzzles of the contest.	11. Non-Consecutive Squeeze

How well did you like the theme of the contest?	I really liked the theme
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Fairly Nice
Your 3 most favorite puzzles of the contest.	9. Thropki

How well did you like the theme of the contest?	I somewhat liked the theme
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Very nice
Your 3 most favorite puzzles of the contest.	13. Triangular Sums
Your 3 most favorite puzzles of the contest.	9. Thropki
Your 3 most favorite puzzles of the contest.	14. Arrowhead

What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Very nice
Your 3 most favorite puzzles of the contest.	5. Anti-Diagonal
Your 3 most favorite puzzles of the contest.	6. Outside Sums
Your 3 most favorite puzzles of the contest.	4. Trio

How well did you like the theme of the contest?	I really liked the theme
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Very nice
Your 3 most favorite puzzles of the contest.	8. Thropki
Your 3 most favorite puzzles of the contest.	7. Max/Min Triplet Sums
Your 3 most favorite puzzles of the contest.	6. Outside Sums

How well did you like the theme of the contest?	I really liked the theme
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Very nice
Your 3 most favorite puzzles of the contest.	5. Anti-Diagonal
Your 3 most favorite puzzles of the contest.	4. Trio
Your 3 most favorite puzzles of the contest.	1. Classic

How well did you like the theme of the contest?	I really liked the theme
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Fairly Nice
Your 3 most favorite puzzles of the contest.	11. Non-Consecutive Squeeze
Your 3 most favorite puzzles of the contest.	12. Renban Squeeze
Your 3 most favorite puzzles of the contest.	14. Arrowhead

How well did you like the theme of the contest?	I really liked the theme
What was your opinion of the distribution of easy/hard puzzles?	Just right
What did you think about the puzzle quality of the test?	Very nice
Your 3 most favorite puzzles of the contest.	14. Arrowhead
Your 3 most favorite puzzles of the contest.	6. Outside Sums

How well did you like the theme of the contest?	I really liked the theme
What was your opinion of the distribution of easy/hard puzzles?	Too many medium difficult puzzles
What did you think about the puzzle quality of the test?	Very nice
Your 3 most favorite puzzles of the contest.	12. Renban Squeeze
Your 3 most favorite puzzles of the contest.	5. Anti-Diagonal
Your 3 most favorite puzzles of the contest.	11. Non-Consecutive Squeeze