In Conway's life, any stable pattern, usually assumed to be finite and nonempty. For the purposes of enumerating still lifes this definition is, however, unsatisfactory because, for example, any pair of blocks would count as a still life, and there would therefore be an infinite number of 8-bit still lifes. For this reason a stricter definition is often used, counting a stable pattern as a single still life only if its islands cannot be divided into two nonempty sets both of which are stable in their own right. Compare pseudo still life.

The requirement that a still life not be decomposable into two separate stable patterns may seem a bit arbitrary, as it does not rule out the possibility that it might be decomposable into more than two. This is shown by the patterns in the following diagram, both found in September 1998. On the left is a 33-cell pattern (by Matthew Cook) that can be broken down into three stable pieces but not into two. On the right is a 44-cell pattern (by Gabriel Nivasch) that can be broken down into four stable pieces but not into two or three. (Note that, as a consequence of the Four-Colour Theorem, four is as high as you need ever go.) It is arguable that patterns like these ought not to be considered as single still lifes.

        ..................O......
        ..............OO.O.O.....
        ..OO.OO.......O.OO.OOO...
        .O.O.OO...............O..
        .O.............OO.OO.OO..
        OO..OO.O.......O...O.O...
        O...OO.OOO......O.O...O..
        .O........O....OO.OO.OO..
        ..O......OO....O.........
        ...O.OO.O.......O.OO.OO..
        ....OO.OO......OO.O.OO..O
        .......................OO

Still lifes have been enumerated by Conway (4-7 bits), Robert Wainwright (8-10 bits), Dave Buckingham (11-13 bits), Peter Raynham (14 bits) and Mark Niemiec (15-24 bits). The resulting figures are shown below. (These figures shouldn't be affected by the above discussion of the strict definition of "still life", because it is unlikely that there are any doubtful cases with less than 33 cells.)

         4        2
         5        1
         6        5
         7        4
         8        9
         9       10
        10       25
        11       46
        12      121
        13      240
        14      619
        15     1353
        16     3286
        17     7773
        18    19044
        19    45759
        20   112243
        21   273188
        22   672172
        23  1646147
        24  4051711

Source: Life Lexicon by Stephen Silver
url: http://www.cs.jhu.edu/~callahan/lexiconf.htm

Still Life are an emo band from Winnetka,California and formed in 1990. They're unique in that they're one of the few emo bands of the early 1990s to still be together, producing music that hasn't given in to 'punk' or pop concessions. They're a trio consisting of brothers David and Chris Pitzel, and Paul Rauch.

Discography:

Additionally, the self-titled 7", Slow Children At Play and the split 7" with Evergreen are collected on LP and CD as Slow Children At Play and Beyond, which was released by Sunflower Tribe.

Log in or register to write something here or to contact authors.