Thx for explanation.

Any suggestion?

Just an idea of lotto (6/45): *
Any 3 digits from txid added togheter <= 45

add digit 1,2,3 for number 1
add digit 3,4,5 for number 2...
if number x = any previous number
do something fair enough to make it different

• Provide simple webpage to calculate txid into 6 decimal numbers so lottery participants can easily check what is on their coupon.
• Use Steemit post as a lottery machine using txid
  https://steemd.com/tx/1642065ca9a5b13d16d4b80209b32f31ec849d0b
• Make it more fair than traditional one

You'll need to automate paying process for that, because of many winners.