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A173061
Arises in classification of base sequences.
0
1, 1, 1, 1, 3, 4, 5, 17, 27, 44, 98, 84, 175, 475, 331, 491, 1721, 2241, 1731, 4552, 3442, 3677, 15886, 6139, 10878, 19516, 10626, 22895, 31070, 18831, 19640
OFFSET
0,5
COMMENTS
Column 2 of Djokovic, p.3, Table 1: Number of equivalence classes of BS(n + 1, n). From the abstract of the paper: "Base sequences BS(n+1,n) are quadruples of {1,-1}-sequences (A;B;C;D), with A and B of length n+1 and C and D of length n, such that the sum of their nonperiodic autocorrelation functions is a delta-function. The base sequence conjecture, asserting that BS(n+1,n) exist for all n, is stronger than the famous Hadamard matrix conjecture. We introduce a new definition of equivalence for base sequences BS(n+1,n) and construct a canonical form. By using this canonical form, we have enumerated the equivalence classes of BS(n+1,n) for n <= 30. Due to excessive size of the equivalence classes, the tables in the paper cover only the cases n <= 12."
LINKS
Dragomir Z. Djokovic, Classification of base sequences BS(n+1,n), arXiv:1002.1414 [math.CO], 2010.
Dragomir Z. Djokovic, Classification of base sequences BS(n+1,n), International Journal of Combinatorics, Vol. 2010, Article ID 851857, 21 pages, 2010.
Dragomir Z. Djokovic, Erratum to "Classification of base sequences BS(n+1,n)", International Journal of Combinatorics, Vol. 2010, Article ID 842636, 2 pages, 2010.
CROSSREFS
Sequence in context: A290014 A298225 A278919 * A174326 A224890 A263810
KEYWORD
nonn,more
AUTHOR
Jonathan Vos Post, Feb 09 2010
STATUS
approved