Sudoku Puzzles

Rip ... shred ... munch ... munch ...

Have a wonderful weekend, everyone!

Love that little plant!

Unfortunately there were no 'beans' on it at the time. It was growing outside a chocolate factory though!

What a wonderful way to end the week. Yummmm!

I could not do this one. However, I did find two backdoors:
6 in f9 gives UP=81 with basic techniques.
5 in i3 gives UP=50, then colouring on 9 gives UP=81.
Best regards, Neil

Hi Neil.The chains seemed to get longer and longer.I only got to UP36. Maybe someone can find a continuation:
1. Unique possibilities to 28.
2. If a3=5,a9=6,a7=6,c8=1 and 14 have no place at b3.So a3=4.UP29.
3. If c8=1,b9=5=a5,b5=2=h6,d5=1=g6,a6=7=f2,f7=5,f9=8 and 14 has no place in row More...

Forgot to type out the second last step:
4(A). If h2=2=i5,b5=5=i3,b3=8=i1,d2=4 and bottom middle box is devoid of 8.So e2=2.UP35.

Too tough

Agree with everybody. Very tough. I could only resolve simple dual choices with chains, like cell a3, and make some eliminations (like 4 from e124). Getting b4=4 took a chain invloving may be a dozen cells. The only way for me to eliminate a wrong guess on any useful pair was to play it out. Even More...

Hi All,

From Alfred’s Step 5 at UP 36:

1) a9=5 or a9=6. If a9=6, a7=5, so either way, a5<>5.

2) b5=2 or b5=5. If b5=2, i5=5, i3=2, h6=2, h5=1, i1=8, b6=8 (& cg6=69), a6=7, f5=7, e1=7, b3=5 & all candidates are eliminated from c1, so b5=5. To UP 46.

3) More...

Hi Brenda,

After your step 2 (and all Alfreds steps to UP=36) I could only get to UP=39 (all in column b), but you got to UP=46 - can you tell me what I may have missed. Many thanks.
best regards, Neil

You're right, Neil. MY UP40 was invalid. Alfred caught that and I put in a step, or a three-part step, to rescue the solution. Alfred also found some shorter chains in the solution above. He'll be posting repaired version shortly. Sorry I didn't answer you sooner;I didn't know anyone was still watching this one.

Hi Brenda, I'm still watching!. Best regards, Neil

Following Brenda's above submission,Brenda and I have collaborated to come up with this continuation:
Typo in my Step 2. "a7=9" (not a7=6).
In my Step 4(A),after i5,add "=e3".
Note that 7s are locked at af5,due to the logic of my step 4.
Brenda's Step 2).Proves More...

Tough one.
Over an hour to solve.

Hi Alfred and Brenda,

Thanks for your solution. I also got to UP=52, but could not find the next one.

Best regards, Neil

SE=9.1