This is the wrong forum for this topic, having said that I found this:

The Kokonotsu Puzzle

The nine letter word “Kokonotsu” in Japanese means simply “nine.” (The word is pronounced “kokonots” – coconuts – the “u” being silent) The puzzle consists of nine 3x3 boxes forming an 81-field matrix. The object is to place nine different objects in each of the nine 3x3 boxes, filling horizontal rows and vertical columns as well as the major diagonals, creating symmetry, harmony and completeness. Typically some numbers – two, three or four – are provided by the puzzlemaker in each nine-square box at the start. The more numbers provided the easier the puzzle.

KOKONOTSU SuperSudoku adds dimensions and challenges not found in ordinary sudoku. Puzzle players who’ve tried both don’t want to go back to “ordinary” sudoku. Generic sudoku puzzles only require the player to fill in rows, columns and 3X3 boxes. Kokonotsu adds a 4th and 5th dimension: the two diagonals and a hidden Magic Puzzle Heart (MagicNine) consisting also of nine numbers that clever players will find and use to help them solve the puzzle more quickly. Each solution to a Kokonotsu puzzle is practically unique. With the number of variations in the quadrillions there is virtually no chance of repetitions.

Sudoku puzzles originated in the 18th Century in Europe, they were known then as "Latin Squares.” In the USA the puzzle was called "Number Place," and from there it was introduced into Japan, as “sudoku,” in the 1980s by the publisher Nikoli Inc. loosing some of its symmetry, Sudoku is a made-up name, meaning single numbers that has become generic.

While sudoku and Kokonotsu are both great puzzles, I must point out that they are totally different in origin, philosophy and objective. Please do not misunderstand: Sudoku is an excellent puzzle, and people’s appetite for quick brain-teasers is again made evident by the tremendous instant success of sudoku in Britain and elsewhere. If it is just a puzzle one wants, then sudoku is great. However, for challenging puzzles that are FUN to solve, calling on one’s total powers of logic, reasoning and strategy, Kokonotsu dubbed the Super Sudoku Puzzle, cannot be surpassed.

At:

http://www.kokonotus.info/Listing.htmlIt's not clear but I think that the extra dimension or Magic Puzzle Heart could be the nine center numbers of each 3x3 box.

MCC