Random Generator

buying propecia california casino indian barona casino cheap delivered find fl phentermine casino guide casino microgaming online snorting valium propecia hair casino royale ameristar casino casino hotel casino game book casino sport casino online tournament buy link onlinehtml xanax xanax00procom casino horseshoe bonus casino code online cheap phentermine yellow casino free game online slot best bonus casino online casino palm casino fallsview casino english harbour online buy link online traxto xanax casino hard rock injecting valium propecia effects ativan drug lorazepam cheap 37 5 phentermine picture propecia result cheap herbal phentermine valium vs vicodin casino gaming online 37 5mg cheap phentermine buy cheap com h1 phentermine phentermine ripway casino game online poker casino gambling line online propecia side effects casino riverside borgata casino casino fun online play casino gambling guide online casino hotel palm valium without prescription order propecia online order cheap phentermine online overnite phentermine cheap order by valium iv casino online slot casino com online bonus casino casino flash online casino free online slot get phentermine cheap valium use cheap phentermine pill cheap order phentermine prescription casino gaming cheap cod extremely phentermine buy link nowcom online xanax casino greektown buy link online sitekreatorcom xanax casino chip indication of valium cheap prescription diet pill phentermine canadian casino online valium dosage casino choctaw propecia study valium half life valium side effects buy link onlinefansto xanax buy doctor xanax bingo casino free game online play propecia online brand buy online xanax cheap phentermine without rx casino free online play buy online upjohn xanax ativan anxiety long term side effects of propecia casino hotel las vegas propecia impotence casino new york ativan birth defect cheap phentermine no prior prescription cheapest cheap phentermine casino deposit new no online ativan dose lethal buy xanax legally ativan and alcohol viagra medication prescription levitra cialis propecia casino craps online casino thunder valley casino online play casino online wagering ativan forum buy overseas xanax casino in las vegas casino links casino on net ativan for depression casino golden online palace canada cheap phentermine ativan addiction buy xanax cod propecia before and after buy cheap lowest phentermine price casino grand online casino free game online valium online ativan attack medication online order panic buy propecia online how propecia works buy insurance medication without xanax casino eagle soaring valium sale casino gambling internet online cheap online order phentermine online casino game cheap phentermine no prescription needed buy buy target xanax xanax casino vegas propecia result casino deposit no propecia and woman buy link member spacesmsncom xanax casino slot online prescription propecia baldness hair lasercomb loss propecia casino news online casino commerce casino payout addicted to ativan casino hard rock seminole casino pechanga propecia sale propecia picture propecia cost buy xanax online pay by check casino fortunelounge online 2mg buy generic xanax buy xanax overnight propecia work casino online poker casino hotel paris propecia body building advice casino online cheap phentermine no prescription required propecia vs rogaine picture pill valium casino forum online ativan ativan buy cheap online valium versus xanax ativan benefit casino game online play cheap est phentermine casino directory gambling online casino internet what does valium do ativan and pregnancy 2005com buy link onlinebuy xanax casino download free online blogspirit cheap com online phentermine buy cheap link onlinecom xanax xanax does effects propecia side work capri casino isle casino gambling advanced casino conscious gambling investor online roulette system tax technique ultimate winning ativan effects hair loss propecia best price for propecia ativan combining neurontin tramadol get propecia cache casino creek order propecia cheap phentermine table casino guide online casino online review california casino casino free valium ativan casino poker buy online prescription propecia vaniqa viaga xenical propecia patent propecia effectiveness cheap phentermine online propecia rogaine propecia patent expiration casino casino casino online top casino winner propecia hair loss treatment generic propecia canada casino wager loss propecia casino las vegas best casino buy no online prescription xanax propecia alternative The Random Generator is BPS's name for the algorithm used to generate the sequence of tetrominoes in Tetris brand games that follow the Tetris Guideline.

Random Generator generates a sequence of all seven one-sided tetrominoes (I, J, L, O, S, T, Z) permuted randomly, as if they were drawn from a bag. Then it deals all seven tetrominoes to the piece sequence before generating another bag. There are 7!, or 5,040, permutations of seven elements, and it is believed that Tetris assigns a nearly equal probability to each of these, making it much less likely that the player will get an obscenely long run without a desired tetromino. It can produce a maximum of 12 tetrominoes between one I and the next I, and a run of S and Z tetrominoes is limited to a maximum of 4. Exception: In Random Generator as implemented in Tetris The Grand Master Ace, the first piece of the first bag is always I, J, L, or T, just as in the traditional TGM randomizer.

Despite the generic sounding name, presumed employees of BPS are known to treat the term "Random Generator" as a unique name, referring only to this particular algorithm.

Snake sequences
There are two "snake" tetrominoes, called S and Z. As only two snakes will be in a given bag, a sequence of more than two snakes must cross the "seam" between bags. The probability of the next two bags having a sequence of four consecutive snakes, the maximum possible, is 1/(7*6*7*6) for SZSZ and likewise for SZZS, ZSSZ, and ZSZS, for a total of 1/441. But the probability of these being your three next pieces are 1/441 times the probability of being at position 6 in a bag, so the probability of the next four pieces being SZSZ are 1 in 3087.

Define a "2|1 combo" as chosen sixth and seventh pieces in one bag and first piece in next bag, and a "1|2 combo" as chosen seventh piece in one bag and first and second pieces in next bag. Define a "snake" as the S tetromino or the Z tetromino.

The probability of any 2|1 combo (e.g. SZ|Z) is 1/(7*6*7) = 1/294. There are four different 2|1 combos containing all snakes (SZ|Z, SZ|S, ZS|Z, and ZS|S), so the probability of getting a 3-snake 2|1 in your next two bags is 4/294. But the probability of being at the sixth piece in a bag, where your next three pieces are a 2|1, is 1/7, making the probability of being at a three-snake 2|1 equal to 4/(294*7) = 2/1029. By symmetry, the 1|2 probabilities are exactly the same: 2/1029. So for Random Generator, this makes a 1 in 257 chance of your next three tetrominoes being snakes.


 * To do: compare with odds for TGM randomizer