Combinatorics PRO vs Brushwright

Finally there is the app that provides all 6 variations of combinatorics with step by step solutions: - permutation without repetition: Arranging elements without repetition. - permutation with repetition: Arranging elements with repetition. - combination without repetition: Selecting elements without considering the order. - combination with repetition: Selecting elements with consideration of the order. - variation without repetition: Arranging elements with fixed length without repetition. - variation with repetition: Arranging elements with fixed length with repetition. You only have to enter your values k and n. The values must be entered as natural numbers. The only exception is the k value for permutation with repitition. This requires several k values, which must be entered separated by semicolons. All calculations are stored in the history. The final solution can be shared. [ Contents ] - all 6 variations of combinatorics - results are calculated and shown in detail - history to save the input - detailed solution - natural numbers are supported - no ads! [ Usage ] - there are fields for entering values using a special keyboard - multiple k values can be entered using the semicolon key - press the check mark button at the bottom right to start the calculation - if values are missing, the corresponding field is highlighted in yellow - if the values are incorrect, the affected field will be highlighted in red - a short message explains why a value is incorrect - the entries in the history can be deleted or sorted - if you select an entry in the history, it will be automatically loaded for the calculation - the whole history can be deleted by pressing a button - solutions can be shared

The right words. Every stroke. Brushwright is an independent study app for Chinese vocabulary at HSK levels 1, 2 and 3. Learn words with Hanzi, pinyin and English meanings, listen with your device's Chinese voice, practice stroke order, and review with spaced repetition. WHAT YOU CAN DO - Read: browse available words with Hanzi, pinyin, English meanings and example sentences where available. - Listen: hear Chinese text with your device's built-in text-to-speech voice. - Write: watch the stroke order of available characters, then trace the strokes yourself. Writing is shown only for levels where it is available. - Review: rate words and come back to them on a spaced-repetition schedule. Your progress, review schedule and settings are stored on your device. - Quick match: a one-minute matching game with words you have learned. It is extra practice and does not change your review schedule. - After a session: check the new words with a short quiz, or trace their characters. This is extra practice and does not change your review schedule. - Your plan: choose your study level (HSK 1-3) and an optional exam date, and Brushwright plans each day. See your study days and progress on the summary. - Practice tests: short timed tests in Brushwright's own format, with listening and reading sections. They are not the official exam and do not copy its format or questions. Results are for practice only and are not an exam score or a prediction of one. - Remind: set an optional local study reminder (notification permission needed). FREE AND PAID - Level 1 is free. - Preview selected lessons of levels 2 and 3 before you buy. - Level Pass: a one-time purchase that unlocks one level (HSK 2 or HSK 3). - Exam Season (every 3 months, with a 7-day free trial for eligible new subscribers) and Monthly: auto-renewing subscriptions that unlock every level available in the app (currently HSK 1-3). Prices are shown in the app and in the App Store before you buy. - No ads. Levels 4-6 are not available yet and have no announced date. Buying never unlocks unfinished content. Use Restore purchases if you reinstall. HOW CONTENT IS MADE All content is original. It is written with AI assistance and checked by an AI review panel plus automated validation. This is AI review, not certification by human native speakers, so mistakes can happen. Use Report a mistake on any item and we will look at it. GOOD TO KNOW - Listening uses your device's voice. Quality depends on your device, and some voices need internet. Brushwright does not record your voice or judge your pronunciation. - Practice tests cover listening and reading only; speaking and free writing are not scored. - Study progress is not synced between devices. - Sharing usage data is optional and off by default. - For ages 13 and up. SUBSCRIPTION TERMS Subscriptions renew automatically unless canceled at least 24 hours before the end of the current period. Manage or cancel in your Apple ID account settings (Settings > your name > Subscriptions). Payment is charged to your store account. Uninstalling the app does not cancel a subscription. Privacy Policy: https://appdiscovery360.com/apps/brushwright/privacy Terms of Use: https://appdiscovery360.com/apps/brushwright/terms HSK is a trademark of its respective owner. Brushwright is not affiliated with or endorsed by CTI (Chinese Testing International) or CLEC. Brushwright is not an official exam, and practice results do not predict or guarantee any exam result.