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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
Take an appealingly illustrated fun test of your perceptual ability, math smarts, and knowledge combinations and probabilities. See how fast your eyes can discern the one sulking face nearly hidden in a large group of smiling "Spikeheads." Figure out how many different shapes went into creating two tessellation patterns. It takes mental gymnastics to rearrange a human tower of 36 red and blue acrobats so that they fulfill a set of rules about where they stand and who they stand next to. Calculate how many different ways the eight Knights of the Round Table can be seated without anyone having the same two neighbors more than once. There's also fascinating background on the theoretical principles that underlie the solutions
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birth defects, or other reproductive harm.
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⚠️ 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.