The procedure graycode computes and returns a list containing all $2^n$ n-bit integers in a graycode order starting at zero.

A graycode order is such that each successive pair of integers differ in only one bit in their binary representations.

The command with(combinat,graycode) allows the use of the abbreviated form of this command.

$\mathrm{with}\left(\mathrm{combinat}\,\mathrm{graycode}\right)$

$\left[\mathrm{graycode}\right]$

$\mathrm{graycode}\left(0\right)$

$\left[0\right]$

$\mathrm{graycode}\left(1\right)$

$\left[0\,1\right]$

$g≔\mathrm{graycode}\left(3\right)$

$g≔\left[0\,1\,3\,2\,6\,7\,5\,4\right]$

$\mathrm{printf}\left(\mathrm{cat}\left(\mathrm{`\$`}\left(\mathrm{`\; \%.3d`}\,8\right)\right)\,\mathrm{op}\left(\mathrm{map}\left(\mathrm{convert}\,g\,\mathrm{binary}\right)\right)\right)$

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