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%I #17 Dec 06 2012 23:15:07
%S 245,1,12,14,145,15,124,1245,125,24,10245,101,1012,1014,10145,1015,
%T 10124,101245,10125,1024,120245,1201,12012,12014,120145,12015,120124,
%U 1201245,120125,12024,140245,1401,14012,14014,140145,14015,140124,1401245
%N Braille natural numbers (including zero), using "0" as digit concatenation mark.
%C Let "0" be the digit concatenation mark, it can be replaced with a "SPACE" as well.
%C XO OO OO OX OO OO
%C Let us define OO-->1; XO-->2; OO-->3; OO-->4; OX-->5 and OO-->6.
%C OO OO XO OO OO OX
%D L. Braille, Method of writing words, music and plain songs by means of dots, for use by the blind and arranged for them, 1829.
%H PharmaBraille, <a href="http://www.pharmabraille.com/pharmaceutical-braille/braille-alphabet.htm">Pharmabraille</a>
%F Let a(0)=245, a(1)=1, a(2)=12, a(3)=14, a(4)=145, a(5)=15, a(6)=124, a(7)=1245, a(8)=125, a(9)=24, then a(n'_n''_..._n''''') = a(n'0n''0...0n'''''), where any [n]''...' is an element of [0,1,2,3,4,5,6,7,8,9].
%e a(0)=245, a(8636)=12501240140124, etc.
%K base,easy,nonn
%O 1,1
%A _Marco Ripà_, Dec 04 2012