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A066330
Binary string which equals n when 1's, 2's, 4's and 8's bits have weights 1, 2, 4, 5 respectively, while the other bits have their usual weights. -1 if no such string exists.
1
0, 1, 10, 11, 100, 1000, 1001, 1010, 1011, 1100, 1101, 1110, 1111, -1, -1, -1, 10000, 10001, 10010, 10011, 10100, 11000, 11001, 11010, 11011, 11100, 11101, 11110, 11111, -1, -1, -1, 100000, 100001, 100010, 100011, 100100, 101000, 101001, 101010, 101011, 101100, 101101, 101110, 101111, -1, -1, -1
OFFSET
0,3
COMMENTS
There are engineering reasons for this encoding, but it is unsatisfactory from a mathematical point of view since 5 could equally well be 101.
REFERENCES
John M. Yarbrough, Digital Logic Applications and Design, West Publishing, 1997, p. 26
CROSSREFS
Sequence in context: A288805 A171782 A038313 * A361336 A348109 A125099
KEYWORD
sign,base
AUTHOR
George E. Antoniou, Dec 15 2001
EXTENSIONS
More terms from Joshua Zucker, Jun 21 2006
STATUS
approved