... by: Dieter

#717 - initially populated cells: 23 = 28,4 %
No solver used, solver = brain.
basics: H7=4, H1=8
populated cells: 25 = 30,9 %

Strategy: numbers 4,2,5,6,7,8 occur most frequently, combine two cells with almost same candidates.
combinations of D9 = (2,4,6,7) and F9 = (2,4,6,8);
after basic checks 7 matrices left: 2/4, 2/6, 2/8, 4/2, 4/6, 6/4 and 7/2.
D9=4 & F9=6 solve with E6=4.

Optimization:
E6=4 & F9=6 solve.

... by: Norman Powell

Take 2: With the correct puzzle.
First you may be glad to know that AS's solver does solve the incorrect puzzle:
000902000000500003000001040008300900600020000050007010260400070070060005004008000 [NB I missed the first cell in my inital copy]
Finding the expected eliminations and resulting in solution found by Bowman's Bingo [Equivalent to Forcing Networks - Solution Found in my solver]
The solving route is longer, mainly because AS deliberately holds back from providing a solution found by Forcing Networks until all other possible methods are exhausted, whereas my solver looks for it in the Forcing Networks and declares a solution as soon as it is found.
Back to the real #717: This is solved resorting to a full implementation of Bowman's Bingo, which tests value after value through levels of trial values, until either a contradiction is found in the base level and an elimination is made or a solution is discovered in the process. Summary of the solution path:
Hidden Singles 8H1 & 4H7
Forcing Networks 1st Pass: Elimnate 1B3 as forces more than one value ON in D6.
Bowman's Bingo: Eliminate 4F5 after 20 trial values over 6 levels of trials.
Solved Cell: 8F5
Forcing Networks: 2nd Pass - 16 eliminations from values being ON causing contradictions: 1A3, 7B1, 2B3, 7C1, 7C4, 4D1, 3E7, 3E8, 3F3, 1G3, 3G7, 9H3, 1J1, 1J4, 9J4, 3J7
Hidden Single: 3F7
Rectangular Elimination: 1E2 and Strong Link E4, H4 would eliminate all the 1's from Box 7 so eliminate.
Forcing Networks: 6 Eliminations suggested before (not used in solution path so not listed) Solution Found [Equivalent to AS's Bowman's Bingo] while testing 7a9 for ON.
Bowman's Bingo is my method of last resort and is designed to return an elimination or the solution.

... by: Frans Goosens

#717

With trial and error

Combination A4=678 and G9=189

************************************************************
A4=6 G9=1 ( A8=8 ) Solved,

Total solving time is : 8 sec.
Number of logical steps is : 548

... by: Serban

# 717 H1=8 H7=4 Basics to 25

1. A9 = C5 =7 solve

2. G6=5 & G9=1 solve

... by: Norman Powell

Apologies, I seem to have an error in copying the puzzle: I solved:
000902000000500003000001040008300900600020000050007010260400070070060005004008000
in the above.

... by: Norman Powell

Apologies, I seem to have an error in copying the puzzle: I solved:
000902000000500003000001040008300900600020000050007010260400070070060005004008000
in the above.

... by: Norman Powell

AS's Solver only finds Hidden Singles 8H1 & 4H7.
My Solver:
Confined to Box: Value 3 confined to Column 5 and Box 2, eliminate 3G5 & 3J5.
[AS's Solver should have picked this up as a Pointing Pair?]
Alternative Inference Chain [Placed before Forcing Networks in my method order]:
3J1 has weak links to both ends of chain, which would cause a contradiction so eliminate.
Chain: -1H3+1H4-2H4+2J4-7J4+7J5-5J5+5J1-
Grouped X-Cycles [Placed after AIC in my methods order]:
1A3 & 1B3 has weak links to both ends of the following chain: which would cause a contradiction so eliminate:
-1H3+1H4-1E4+1[E2 E3]-1D1+1[A1 B1]-
Forcing Network Pass 1: Finds nothing until testing 9C3 for being ON, when it finds the solution:
547932168186574293329681547718346952693125784452897316265413879871269435934758621
[This is equivalent to AS's Bowman's Bingo]
I am not sure why AS's Solver did not proceed further?