If you have any questions, you are always welcome to contact us. We'll get back to you as soon as possible, withing 24 hours on weekdays.
Customer service
All questions about your order, return and delivery must be sent to our customer service team by e-mail at yourstore@yourdomain.com
Sale & Press
If you are interested in selling our products, need more information about our brand or wish to make a collaboration, please contact us at press@yourdomain.com
Help
If you have any questions, you are always welcome to contact us. We'll get back to you as soon as possible, withing 24 hours on weekdays.
Customer service
All questions about your order, return and delivery must be sent to our customer service team by e-mail at yourstore@yourdomain.com
Sale & Press
If you are interested in selling our products, need more information about our brand or wish to make a collaboration, please contact us at press@yourdomain.com
Math skills are NOT required for sudoku! You can have fun and sharpen your mind at the same time. Mental games are very good for your memory, they increase your brain power, and help delay dementia and Alzheimer's.VARIETY OF LEVELS: David Karn sudoku books are available in one or a mix of several levels of difficulty. There are six levels (Beginner, Easy, Medium, Hard, Very Hard, and Extreme) and they come in various combinations of those. Please check the title and book cover for details.EASY TO READ AND FILL OUT: Available in various font sizes so that even those with poor eyesight can easily read the numbers. There is a choice of extra large (42pt), large (36pt), regular (24pt), and medium (18pt) font sizes.SOLUTIONS: If you get stuck, there are solutions in the back of the book.BOOK SIZES: You can get our books in the standard large 8.5" x 11" size or a much smaller 5" x 8" travel size that's easy to carry in your purse or backpack. You can take them to work, school, on a roadtrip, or to the beach. And even the small travel edition is available in large print!A GREAT GIFT ??????: Puzzles are perfect gifts for parents, grandparents, elderly, or anyone stuck in a hospital. They make wonderful birthday gifts, stocking stuffers, and are a great value as presents for any occasion.
⚠️ WARNING (California Proposition 65):
This product may contain chemicals known to the State of California to cause cancer,
birth defects, or other reproductive harm.
<div class="dynamic-checkout__content" id="dynamic-checkout-cart" data-shopify="dynamic-checkout-cart"> <shopify-accelerated-checkout-cart wallet-configs="[{"supports_subs":true,"supports_def_opts":false,"name":"shop_pay","wallet_params":{"shopId":73758048501,"merchantName":"Ergodebooks","personalized":true}},{"supports_subs":false,"supports_def_opts":false,"name":"amazon_pay","wallet_params":{"checkoutLanguage":"en_US","ledgerCurrency":"USD","placement":"Cart","sandbox":false,"merchantId":"A1G1ZY975O1T6J","productType":"PayAndShip","design":"C0002"}},{"supports_subs":true,"supports_def_opts":false,"name":"paypal","wallet_params":{"shopId":73758048501,"countryCode":"US","merchantName":"Ergodebooks","phoneRequired":true,"companyRequired":false,"shippingType":"shipping","shopifyPaymentsEnabled":true,"hasManagedSellingPlanState":false,"requiresBillingAgreement":false,"merchantId":"L873BZSC9NMQS","sdkUrl":"https://www.paypal.com/sdk/js?components=buttons\u0026commit=false\u0026currency=USD\u0026locale=en_US\u0026client-id=AbasDhzlU0HbpiStJiN1KRJ_cNJJ7xYBip7JJoMO0GQpLi8ePNgdbLXkC7_KMeyTg8tnAKW4WKrh9qmf\u0026merchant-id=L873BZSC9NMQS\u0026intent=authorize"}}]" access-token="c0f52a66b386e9fa5c0ab4c2febc737c" buyer-country="US" buyer-locale="en" buyer-currency="USD" shop-id="73758048501" cart-id="c3ec487ee625be74d6727d613fbdf265" enabled-flags="["32a68cd0","a1c7ccbe","ce346acf","c0874428"]" > <div class="wallet-button-wrapper"> <ul class='wallet-cart-grid wallet-cart-grid--skeleton' role="list" data-shopify-buttoncontainer="true"> <li data-testid='grid-cell' class='wallet-cart-button-container'><div class='wallet-cart-button wallet-cart-button__skeleton' role='button' disabled aria-hidden='true'> </div></li><li data-testid='grid-cell' class='wallet-cart-button-container'><div class='wallet-cart-button wallet-cart-button__skeleton' role='button' disabled aria-hidden='true'> </div></li><li data-testid='grid-cell' class='wallet-cart-button-container'><div class='wallet-cart-button wallet-cart-button__skeleton' role='button' disabled aria-hidden='true'> </div></li> </ul> </div> </shopify-accelerated-checkout-cart> <small id="shopify-buyer-consent" class="hidden" aria-hidden="true" data-consent-type="subscription"> One or more of the items in your cart is a deferred, subscription, or recurring purchase. By continuing, I agree to the <span id="shopify-subscription-policy-button">cancellation policy</span> and authorize you to charge my payment method at the prices, frequency and dates listed on this page until my order is fulfilled or I cancel, if permitted. </small> </div>
Stay in the know
Subscribe to our newsletter and stay updated on latest offers, discounts and events near you.
For MAP (Minimum Advertised Price) violations and Intellectual Property (IP) or Trademark concerns, please contact:
support@ergodebooks.com
⚠️ California Proposition 65 Warning: Some products sold on this website may expose you to chemicals known to the State of California to cause cancer, birth defects, or other reproductive harm. For more information, visit www.P65Warnings.ca.gov.