Blockhash RNG immune to tampering for PoS and PoW

RNG.sol

contract RNG {
  bytes32 encrypted_seed;
  bytes32 revealed_seed;
   bytes32 revealed_secret;
   uint odds;
   uint bet_blocknumber;
   uint bet_input;
   bool bet_made;
   uint bet_result;
   string log;
 
 function RNG(){
   odds=100;
   //example seed
   //made by secret = “0x006ee0953c7Bb75CA6De27f58b5512390B1C4d6a” 
   // seed=”0x7cB57B5A97eAbe94205C07890BE4c1aD31E486A8"
   encrypted_seed=”0x903e88616c7587ec063b5c79f4f5aad24de25f1e149a87edeeb964cbfbf70b38";
 }
 
 function bet(uint integer_0_to_odds_minus_1){ 
  if (bet_made) throw;
  if (integer_0_to_odds_minus_one <= odds) {
    bet_input = integer_0_to_odds_minus_one;
    bet_blocknumber=block.number;
    bet_made = true;
  }
 }
 
 function reveal(bytes32 rev_seed_, bytes32 rev_secret_) {
  //verify that bet has been made
  if (!bet_made) throw;
  //verify that the block of the bet has been mined.
  if (block.number>bet_blocknumber){ 
  //verify if the revealed seed and secret match with encrypted committed hash.
    if ( sha3(rev_seed_,rev_secret_)!=encrypted_seed) throw;
    revealed_seed=rev_seed_;
    revealed_secret=rev_secret_;
  }
  else throw;
  
  //The EVM only stored the last 256 blockhashes
  // After that it’s too late to reveal and an alternative resolution should be provided here
  if (block.number>bet_blocknumber+250) throw;
  //compute pseudo RNG
  bet_result=uint(sha3(revealed_seed,block.blockhash(bet_blocknumber)))%(odds);
  //solve bet
  if (bet_input == bet_result){
  log=”You won”;
  }
  else{
  log=”You lose”;
  }
 }
}