An unmagic square
notmagic.2n.Rd
Returns a square of order \(n=2m\) that has been claimed to be magic, but isn't.
Note
This took me a whole evening to code up. And I was quite pleased with the final vectorized form: it matches Andrews's (8 by 8) example square exactly. What a crock
Examples
notmagic.2n(4)
#> [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8]
#> [1,] 1 16 17 32 33 48 49 64
#> [2,] 63 50 47 34 31 18 15 2
#> [3,] 3 14 19 30 35 46 51 62
#> [4,] 61 52 45 36 29 20 13 4
#> [5,] 5 12 21 28 37 44 53 60
#> [6,] 59 54 43 38 27 22 11 6
#> [7,] 7 10 23 26 39 42 55 58
#> [8,] 57 56 41 40 25 24 9 8
is.magic(notmagic.2n(4))
#> [1] FALSE
is.semimagic(notmagic.2n(4))
#> [1] FALSE