There are some strategies that use one single number
and the automatic + on win progression,
which corresponds in this case, a Single-Number-Martingale.
As quantitatively only one Single Number is played,
this can be an answer to the question derived after the march or the relevance of chance selection.
Here are the results overviews of these one-single-Strategies to compare:
the Zero +
the Regular +
the Last +
the Restant +
the Favorite +
the Random +