Tom's Fewest Moves Challenge: 4x4x4

The results are announced!

This competition is to find the shortest solutions to five previously-selected random positions of Rubik's Revenge.

There are two main categories: computer and human. You are welcome to compete in either or both. Within each category, there will be two metrics: outer block turn and block turn. In each metric both quarter and half turns will be considered a single turn. Full cube moves (x, y, and z) will not count against your score.

Overall scoring will be by trimmed average of five. For each individual position, only your best solution will be considered; from the five scores for the five positions, the largest and smallest will be eliminated, and the average of the remaining three will be your score.

The main contest will run from 9PM, San Francisco time, on May 13th, 2014 until noon, San Francisco time, on July 15th, 2014. Submissions after the end date are not eligible for prizes.

Only the computer category will be awarded prizes (although the winners of the human category will receive the appropriate acclaim). The overall winner in the block turn metric will receive a cash prize of $75. The overall winner in the outer block turn metric will receive a cash prize of $75. Runners up in both metrics will receive $25 each.

Submission shall be either through the form on this page or through the JavaScript applet. I encourage you to use the JavaScript applet. The following information is required for each entry:

The move notation will be as follows: Lower case face names (such as u) are treated as twists of the two outer layers; you must use 2U, for instance, to indicate an inner slice turn. Double slice turns (E, M, S, N), single slice turns (2U), face turns (U), wide turns (Uw, 3Uw), and full cube rotations (x, y, and z) are all accepted. Spaces between moves are accepted. To indicate a half-turn, use the numeral 2 (as in U2); to indicate a counter-clockwise or inverse turn, use the apostrophe (as in Uw'). Meta-syntax, such as parentheses and brackets will not be accepted; you must expand these out yourself. The only acceptable characters are from the set U F R D B L u f r d b l w x y z E M S N 2 ' and space. You may use slice turns in solutions for the outer block turn metric; any such will be counted as two moves.

All entries will be considered for all positions and all metrics. Only those entries that actually solve one of the given positions will be considered. It is your responsibility to verify this; we will not be validating solutions on submission. Use the applet if you have any doubt.

Any computer code used need not be your own. You do not need to share your computer code or any ideas, although I encourage you to do so.

There are no restrictions on postings about this contest, although I encourage you to be considerate. You may post techniques, or ideas, or your personal scores.

I will post, at random times, standings (without actual scores) and intermediate prizes (such as, for instance, gift certificates for cube stores). I may award such prizes for arbitrary categories (best solution for a particular position, or best human solve).

You may not use computer search for a human solve. I have no way to enforce this, which is why there are no monetary prizes for human solves, but am relying on the spirit of the cube community.

A human solve should not be obviously related to the scramble algorithm.

I reserve the right to terminate this contest early, interpret the rules as I see fit, and disqualify individuals on any basis whatsoever.

The scrambles are:
1) U L F D B2 F2 U2 R' F2 R2 B2 D2 R' D2 L B R D' U' R2 L' F L2 D F2 Uw2 B Uw2 F' R' Fw2 F' Rw2 R' B' R2 Fw2 L' Uw L2 D' B2 U Rw' Fw Uw' F' Uw' U' R B R U
2) F U R U B' D R U2 R B U2 L D' F' U2 L R B2 D2 R D2 R' B2 Uw2 Rw2 R' D L D2 L2 R Fw2 U L2 B' U Fw' L D2 F2 Rw' Fw2 Rw' Uw' Fw2 Rw D' F U F D
3) F D B D L' U2 F U2 D' B2 F L B F U2 L' F2 R' U2 F2 L B2 R2 B2 Fw2 Uw2 D' B F' Uw2 B R2 Fw2 Uw2 D' U2 Rw U L B U2 Uw' F' Rw2 R2 Fw F2 Uw' B' L B U L
4) R F D L D2 F D U B2 F2 L' B2 U F2 L D2 U2 L U2 R B2 L B2 Uw2 Rw2 F U2 R' B' Uw2 F2 R Uw2 F' Uw' L2 D2 L B2 R' Uw' D2 Fw' Rw R Uw' L2 B D F D
5) F U F U F2 R2 D' R2 B2 D B2 D2 B2 R2 U' F R F' B' D' R2 D' L' Uw2 F' Uw2 U2 Rw2 Fw2 B D F' B D' L2 B2 Rw' Fw2 R' U B U' Rw' Uw R' Fw B U L D R
You may submit your solution here.

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