YABTC-BiTCoin Lottery

YABTCL means Yet Another BiTCoin Lottery.
But it isn't just another Bitcoin lottery system, it's the most complete provably fair lottery system available so far.

• Basic Functionality:
•  The draws will occur three times in a week: Tuesdays, Thursdays and Saturdays at 24:00 UTC;
•  In each draw 6 numbers in a total of 67 will be drawn;
•  Tickets price start at 0.001 BTC;
•  You can buy tickets having between 6 to 16 numbers;
•  With each ticket you can win hitting 2 to 6 numbers.

• Pools:
•  The pools are created by the users;
•  There are two types of pools: Share-a-Ticket and Add-a-Ticket;
•  In the Share-a-Ticket pool, the owner buy the tickets and define to how many quotas the total value of the tickets will be divided. The owner can define a service charge for this type of pool;
•  In the Add-a-Ticket pool, the owner define how many tickets can be added to it and how many numbers each ticket can have.

• Draws (All draws are provably fair):
•  One and half hour before the time of the draw, a file will be generated containing all the tickets that will participate in the draw. We will timestamp the SHA256 file hash with a Bitcoin transaction;
•  At the time of the draw, we will check the current Bitcoin block number and the next block will be used to generate the winning numbers;
•  The seeds that will be used to generate the winning numbers are: the block hash (lower case), the block height, the server secret and the SHA256 hash (upper case) of the file with the participating tickets;
•  The winning numbers will only be published after the chosen block having 6 confirmations.

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