Update

We’ve extended the hidden contest for at least two more weeks and added another hint for it.

Besides this hidden contest, there will likely be no new puzzles on the site until May, and a return to a regular schedule will probably still be some time after that. I’ll be using some of this time to close out lots of things that have been pushed back because of the demands of meeting a weekly posting schedule, including the print edition of The Art of Puzzles, the print and electronic editions of The Art of Puzzles 2: Double Trouble, as well as the #1 Fans puzzle promised to our patrons long ago. Thanks again for your patience.

Arrow/Thermo-Sudoku by Prasanna Seshadri

Arrow Thermo-Sudoku by Prasanna Seshadri

PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: H (patron puzzle created for Paul Hlebowitsh)

Author/Opus: This is the 80th puzzle from our contributing puzzlemaster Prasanna Seshadri.

Rules: Standard Arrow Sudoku rules. Also, standard Thermo-Sudoku rules.

Answer String: Enter the 4th row from left to right, followed by a comma, followed by the 9th row from left to right.

Time Standards (highlight to view): Grandmaster = 5:15, Master = 7:45, Expert = 15:30

Solution: PDF

Note: Follow this link for more Arrow Sudoku. Follow this link for more Thermo-Sudoku puzzles. More Arrow and Thermo-Sudoku puzzles can be found in The Art of Sudoku 2.

Site News

I wanted to share some life/site news with you all. Tomorrow I’m starting a new job at Google with their Life Sciences team. I just drove back to California for this unique opportunity, but I am quite far from being settled in.

As a result of this life change, I’m going to be taking an indefinite break from posting regular puzzles here. There may be a few random puzzles posted during this gap, but this past week was the last full week for awhile.

In the interim, there is still an open contest to solve (with a new hint).

And for most of you, there are still hundreds of past puzzles to look through. I’ve made a new archive page where you can readily download everything we’ve posted.

— Dr. S.

The Persistence of Memory by Prasanna Seshadri

The Persistence of Memory by Prasanna Seshadri

(View image directly for larger form.)

PDF

or solve online (using our beta test of Penpa-Edit tools using a composite mode where left click inside cell shades square, left click + drag draws line segment, right click inside cell adds dot, and right click on cell edge adds an x.)

Theme: TYCG (Thank You, Chris Green) — this is a Patron Puzzle reward.

Author/Opus: This is the 79th puzzle from our contributing puzzlemaster Prasanna Seshadri.

Rules: Find a path from one dot to the other by moving horizontally or vertically between adjacent squares. The path cannot touch itself, even diagonally. All highlighted regions must be visited by the path, and may be re-entered. If two or more highlighted regions have the same shape and orientation, then how the path passes through those shapes must be identical. Or see here.

Answer String: Enter the length in cells of the horizontal path segments from left to right in the marked rows, starting at the top. If the path only has vertical segments in the marked row, enter 0. Separate each row’s entry with a comma.

Time Standards (highlight to view): Grandmaster = 4:15, Master = 6:00, Expert = 12:00

Solution: PDF

Fillomino by John Bulten

Fillomino by John Bulten

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between a composite mode for line/edge drawing and a number entry mode.)

Theme: 28 Dice

Author/Opus: This is the 10th puzzle from our contributing puzzlemaster John Bulten.

Rules: Standard Fillomino rules.

Answer String: For each cell in the marked rows/columns, enter the area of the polyomino it belongs to. Enter just the last digit for any two-digit number. Start with the 5th row, followed by a comma, followed by the 9th column.

Time Standards (highlight to view): Grandmaster = 4:30, Master = 7:15, Expert = 14:30

Solution: PDF

Note: Follow this link for other classic Fillomino. If you are new to this puzzle type, here are our easiest Fillomino puzzles to get started on.

Tapa (Cipher) by Carl Worth

Tapa by Carl Worth

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to shift between shading mode, a number entry mode for placing Tapa clues, and the composite Yajilin mode where left click marks cells, right click marks dots in cells or X’s on edges, left click+drag draws lines.)

Theme: Logical

Author/Opus: This is the 8th puzzle from guest contributor Carl Worth.

Rules: Standard Tapa rules, except that the digits have been encoded with a cipher into letters. Each letter represents a different positive integer, for the solver to determine.

Answer String: Enter the length in cells of each of the shaded segments from left to right for the marked rows, starting at the top. Separate each row’s entry from the next with a comma.

Time Standards (highlight to view): Grandmaster = 2:30, Master = 4:00, Expert = 8:00

Solution: PDF

Note: Follow this link for other Tapa variations and this link for classic Tapa. If you are new to this puzzle type, here are our easiest Tapa puzzles to get started on.

Snake Egg by Murat Can Tonta

Snake Egg by Murat Can Tonta

PDF

or solve online (using our beta test of Penpa-Edit tools using a composite mode where left click inside cell shades square, left click + drag draws line segment, right click inside cell adds dot, and right click on cell edge adds an x.)

Theme: Minimalism

Author/Opus: This is the 19th puzzle from guest contributor Murat Can Tonta.

Rules: Locate a snake (a 1 cell-wide path) in the grid whose head and tail are given. The snake can touch itself diagonally, but cannot touch itself orthogonally or revisit any square. Besides the snake, the remaining cells must form exactly nine white areas, one of each size from 1 to 9. Numbers in the grid must be part of white areas of the indicated size.
(Also see here: https://yureklis.wordpress.com/2012/07/02/snake-egg/)

Answer String: Enter the length in cells of each of the snake segments from left to right for the marked rows, starting at the top. Separate each row’s entry with a comma.

Solution: PDF; a solution video is available here.

Time Standards (highlight to view): Grandmaster = 3:15, Master = 4:15, Expert = 8:30

YVGF ol Tenag Svxrf

YVGF ol Tenag Svxrf

CQS

Gurzr: Fcbvyre-serr

Nhgube/Bchf: Guvf vf gur 166gu chmmyr sebz bhe pbagevohgvat chmmyrznfgre Tenag Svxrf.

Ehyrf: Fgnaqneq YVGF ehyrf (jneavat: yvax znl pbagnva fcbvyref!).

Nafjre Fgevat: Ragre gur yratgu va pryyf bs rnpu bs gur funqrq frtzragf sebz yrsg gb evtug sbe gur znexrq ebjf, fgnegvat ng gur gbc. Frcnengr rnpu ebj’f ragel sebz gur arkg jvgu n pbzzn.

Gvzr Fgnaqneqf (uvtuyvtug gb ivrj): Tenaqznfgre = 4:00, Znfgre = 5:15, Rkcreg = 10:30

Fbyhgvba: CQS

Abgr: Sbyybj guvf yvax sbe bgure pynffvp YVGF. Vs lbh ner arj gb guvf chmmyr glcr, urer ner bhe rnfvrfg YVGF gb trg fgnegrq ba.