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A072998
To get a(n), write n in balanced ternary notation (using only digits -1, 0, 1, -1), then change -1's to 0's, 0's to 1's, and 1's to 2's.
2
1, 2, 20, 21, 22, 200, 201, 202, 210, 211, 212, 220, 221, 222, 2000, 2001, 2002, 2010, 2011, 2012, 2020, 2021, 2022, 2100, 2101, 2102, 2110, 2111, 2112, 2120, 2121, 2122, 2200, 2201, 2202, 2210, 2211, 2212, 2220, 2221, 2222, 20000, 20001, 20002, 20010
OFFSET
0,2
EXAMPLE
n balanced ternary a(n)
-----------------------
0........0...........1
1........1...........2
2......1,-1..........2,0
3.......1,0..........2,1
...
11 in base 10 = 11_10 = {1,1,-1} in balanced ternary = 1*3^2 + 1*3^1 - 1*3^0. Add 111 to {1,1,-1} to get a(11) = 220.
CROSSREFS
Sequence in context: A303157 A338994 A217394 * A024629 A235500 A319953
KEYWORD
base,nonn
AUTHOR
Robert G. Wilson v, Aug 15 2002
EXTENSIONS
Corrected by Reinhard Zumkeller, Aug 18 2008
Edited by N. J. A. Sloane, Mar 31 2021
STATUS
approved