Yet Another 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;
– You can buy tickets that must have 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 our 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.