Subscribe!


It is now possible to subscribe to the site, which will get you:
  • one extra "special puzzle" every day, which can be solved any time:
    • Sunday: 6x6 "no-op"
    • Monday: 7x7 twin
    • Tuesday: 8x8 with exponentiation
    • Wednesday: 10x10 (medium)
    • Thursday: 7x7 with negative numbers
    • Friday: 8x8 twin
    • Saturday: 15x15 or 7x7 "no-op" twin from zero
    Each extra puzzle is worth 8 points
  • up to 4 puzzles against the clock of each size (instead of 2)
  • all ads permanently disabled
  • more bonus puzzles
  • the ability to do puzzles of up to 1 month ago (instead of 1 week)

The one year subscription will also get you two free books (as PDF downloads)
(note: these are new books, and not for sale separately):

  • "201 Tricky Calcudoku Puzzles, Extra".
    The 41 difficult puzzles in this book are worth 5 points each.
    (this book is not for sale separately)

  • "102 Large Calcudoku Puzzles, Extra".
    The 32 difficult puzzles in this book are worth 10 points each.
    (this book is not for sale separately)

 New: when you renew your annual subscription, you'll get the book "51 Advanced Puzzles" (also as a PDF download, and also not for sale separately):

The six month subscription will get you one free book (of the first two, specify which one you prefer when ordering).

Subscriptions are not automatically renewed (you can add a new subscription at any time).

Payment is done through Paypal (where you can pay using a Paypal account or credit card; so note that no payment information is stored on this site).

Note: after payment, wait until you return to the site, then your subscription will be started automatically.

One month subscription, all benefits except the free books
$2.49
Note: You have to be logged in before you can subscribe.

Six month subscription, all benefits and one free book
$11.95
Note: You have to be logged in before you can subscribe.

One year subscription, all benefits and two free books
$19.95
Note: You have to be logged in before you can subscribe.

Change currency:    € Euro  |  £ British pound  |  $ US dollar  |  ¥ Japanese Yen

It is also possible to become a subscriber by bank transfer to IBAN NL96INGB0006238302 (BIC/SWIFT code: INGBNL2A) to "Patrick Min Computer Programming", the Netherlands. Don't forget to put your username (!) in the transfer comments, and (for the 6 month subscription) the book you'd like.

Donate

You can also support the site by giving a donation. This will be much appreciated, but is of course not required.