Sudoku Puzzles

Gorgeous! Just when you think you MUST have seen all the most beautiful sunset photos... Thanks!

A beautiful place and a beautiful sunset.

Pretty.

1. Note pair 28 at g5/h4.Unique possibilities to 27.
2. If h4=2,g7=2;if h4=8,h2=4,g7=4.So g7=24,g6=5.UP29.
3. If f3=2=b2,f8=3,b1=8,a1=7=f6,f1=4,f5=1,pair 17 at bc4;row 4 is devoid of 4.So d2=2.UP30.
4. If f6=3,b6=7=a1=f9,e6=9,d5=6=e7,e9=8=c7;top left box is devoid of 7.So f6=7.UP81.

Keep those lovely sunsets and sunrises coming. Can anyone tell me what Alfred's comment is all about?

That was slow, 49:53. Good night all.

Bev, Alfred's comment is the shorthand description of the logical solution to the puzzle.

Like the game Battleship, each of the 81 squares in the puzzle are named by a column and row designation. The difference is that a1 is in the bottom left hand side of the puzzle. Columns are letters More...

maen all! another sailor's delight! yup, these tough one's are tough...i do a lot better if i print them out and work with a pen and pencil in the possibilities.

Hi Alfred,
Basic techniques to 29,so you step 2 is not necessary.
Regards,Sotir

Thanks for the explanation Plum.

Thanks Sotir,but I think I am having one of my blind spots.I can't see how to eliminate 5 from g7,using basic techniques.

Thanks too,to Plum for the detailed explanation of the notation.
Regards Alfred.

44:08

25:22

Clear as mud!
Amazing colours in this sunset.

Hi Alfred,
hp(36)h13,=>h6=1,g6=5.
Regards,Sotir

My path for this one:

1) Start at 22,basic techniques to UP=29
2)YWS:(hp14=1)bce4-(1=nt239)de1d2-(2=np67)ad4,=>bc4<>67.UP=33
3)(2)d2=f3-(2=3)f8-(3 =7)f6-b6=(7-8)b1=(8)b2,=>b2<>2.UP=81

Thanks Sotir;missed the 36 pair.
Your solution is pretty efficient.Although I only found 3 extra UPs from your step 2), (b4=4=c3,c4=1),your step 3) still worked.

Hi Alfred, Sotir and All,
Alfred - 4 in g1 was Sotir's UP=33.
Sotir, I am still amazed at how you spot these chains. I am still studying though.
All, from UP=29 (ie, basic techniques), there is a 'backdoor' of 8 in g1 - gives UP=81 without any problems.
Best regards, Neil

Hi Neil,
You are right.Alfred's step 4 also is not necessary.
Only step 3 d2=2,=>UP=81.But using AIC, first I
had to eliminate c4<>7, to open the path for step 3.,=>UP=81.
Best Regards,Sotir

Thanks Sotir and Neil.
Finally realise:after d2=2,pair 67 at ad4,14 at ac4,triple 369 at acd5,e7=6,c8=8 etc.
Regards,Alfred.

I'll stick to the easier way (at least for me);Logic

SE=8.4

1.SST to UP29
2.(1=239)d12e1-(2)d4=(28')eh4 > -1e4 UP34
3.(2=3)f8-b8=(35'-2)a78=a3 > -2a8f3 UP81