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.

Showing 1-4 of 4 results.

A090899 Number of nonisomorphic indecomposable self-dual quantum codes on n qubits.

Original entry on oeis.org

1, 1, 1, 2, 4, 11, 26, 101, 440, 3132, 40457, 1274068
Offset: 1

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Author

David G Glynn (dglynn(AT)mac.com), Feb 26 2004

Keywords

Comments

Also number of nonisomorphic indecomposable self-dual codes of Type 4^H+ and length n.
Each self-dual (additive) quantum code of length n stabilizes an essentially unique quantum state on n qubits, the 2^n coefficients of which can be assumed to take values in {0,1,-1}. It also corresponds to a "quantum" set of n lines in PG(n-1,2): the Grassmannian coordinates of these lines sum to zero. A related sequence is the number of nonisomorphic (possibly decomposable) self-dual quantum codes on n qubits, A094927.
Also the number of equivalence classes of connected graphs on n nodes up to sequences of local complement ation (or vertex neighborhood complementation) and isomorphism.

Examples

			For four qubits there are two nonisomorphic self-dual quantum codes corresponding to the complete graph and the circuit on four vertices.
		

References

  • David G. Glynn and Johannes G. Maks, The classification of self-dual quantum codes of length <= 9, preprint.
  • D. M. Schlingemann, Stabilizer codes can be represented as graph codes, Quant. Inf. Comp. 2, 307.

Crossrefs

Extensions

a(10)-a(12) from Lars Eirik Danielsen (larsed(AT)ii.uib.no) and Matthew G. Parker (matthew(AT)ii.uib.no), Jun 17 2004

A110302 Number of inequivalent indecomposable self-dual codes of Type {4^H+}_II and length 2n.

Original entry on oeis.org

1, 1, 1, 4, 14, 103, 2926
Offset: 0

Views

Author

N. J. A. Sloane, Sep 09 2005

Keywords

References

  • L. E. Danielsen and M. G. Parker, On the classification of all self-dual additive codes over GF(4) of length up to 12, Preprint 2005.

Crossrefs

A110306 Number of inequivalent (indecomposable or decomposable) self-dual codes of Type {4^H+}_II and length 2n.

Original entry on oeis.org

1, 1, 2, 6, 21, 128, 3079
Offset: 0

Views

Author

N. J. A. Sloane, Sep 09 2005

Keywords

Crossrefs

A105687 Number of inequivalent codes attaining highest minimal Hamming distance of any Type 4^H+ Hermitian additive self-dual code over GF(4) of length n.

Original entry on oeis.org

1, 1, 1, 3, 1, 1, 4, 5, 8, 120, 1, 1
Offset: 1

Views

Author

N. J. A. Sloane, May 06 2005

Keywords

References

  • C. Bachoc and P. Gaborit, On extremal additive F_4 codes of length 10 to 18, in International Workshop on Coding and Cryptography (Paris, 2001), Electron. Notes Discrete Math. 6 (2001), 10 pp.
  • P. Gaborit, W. C. Huffman, J.-L. Kim and V. S. Pless, On additive GF(4) codes, in Codes and Association Schemes (Piscataway, NJ, 1999), A. Barg and S. Litsyn, eds., Amer. Math. Soc., Providence, RI, 2001, pp. 135-149.
  • G. Hoehn, Self-dual codes over the Kleinian four-group, Math. Ann. 327 (2003), 227-255.

Crossrefs

A016729 gives the minimal distance of these codes.
A094927 gives the number of inequivalent codes of any distance.

Extensions

Corrected and extended to 12 terms by Lars Eirik Danielsen (larsed(AT)ii.uib.no) and Matthew G. Parker (matthew(AT)ii.uib.no), Jun 30 2005
Showing 1-4 of 4 results.