cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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.

Original entry on oeis.org

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

Views

Author

George E. Antoniou, Dec 15 2001

Keywords

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

Extensions

More terms from Joshua Zucker, Jun 21 2006