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A220090
Braille natural numbers (including zero), using "0" as digit concatenation mark.
1
245, 1, 12, 14, 145, 15, 124, 1245, 125, 24, 10245, 101, 1012, 1014, 10145, 1015, 10124, 101245, 10125, 1024, 120245, 1201, 12012, 12014, 120145, 12015, 120124, 1201245, 120125, 12024, 140245, 1401, 14012, 14014, 140145, 14015, 140124, 1401245
OFFSET
1,1
COMMENTS
Let "0" be the digit concatenation mark, it can be replaced with a "SPACE" as well.
XO OO OO OX OO OO
Let us define OO-->1; XO-->2; OO-->3; OO-->4; OX-->5 and OO-->6.
OO OO XO OO OO OX
REFERENCES
L. Braille, Method of writing words, music and plain songs by means of dots, for use by the blind and arranged for them, 1829.
FORMULA
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].
EXAMPLE
a(0)=245, a(8636)=12501240140124, etc.
CROSSREFS
Sequence in context: A306981 A164656 A291587 * A013684 A233821 A216233
KEYWORD
base,easy,nonn
AUTHOR
Marco Ripà, Dec 04 2012
STATUS
approved