منابع مشابه
Frequency Squares of Orders 7 and 8
We enumerate frequency squares of orders 7 and 8 and the corresponding isotopism classes. An error in a previous paper by L.J. Brant and G.L. Mullen is discovered and partially corrected.
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A shuffle square is a word that can be partitioned into two identical words. We obtain a short proof that there exist exponentially many words over the 7 letter alphabet containing no shuffle square as a factor. The method is a generalization of the so-called power series method using ideas of the entropy compression method as developped by Gonçalves, Montassier, and Pinlou. 1991 Mathematics Su...
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We investigate Room squares and subsquares. All terminology is as in [6] and [7], and we will assume the reader is familiar with the definitions contained therein. (These include group-divisible designs, transverial designs, and frames.) We will refer to an incomplete Room square of side s missing a subsquare of side t as an (s, t)-incompZefe Room square. It is known that for any odd t, there i...
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We continue with the disucssion from last time. There is no new reading, just the same as last class. Recall that last time we provided a brief overview of LS problems and a brief overview of sketching methods for LS problems. For the latter, we provided a lemma that showed that under certain conditions the solution of a sketched LS problem was a good approximation to the solution of the origin...
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ژورنال
عنوان ژورنال: Annals of Eugenics
سال: 1939
ISSN: 2050-1420
DOI: 10.1111/j.1469-1809.1939.tb02214.x