Talk:Costas array: Difference between revisions

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All Costas arrays of size up to and including 26x26 are known. It is not known whether Costas arrays exist for all sizes. Currently, the smallest sizes for which no arrays are known are 32x32 and 33x33. ?? If I read this my conclusion would be that we know then up to 31x31. So why say whe know then up to 26x26. —Preceding unsigned comment added by 87.212.47.202 (talk • contribs)

These statements are not in conflict. The first statement says we have a complete list of Costas arrays of size 26×26 or smaller. The second statement says we know at least one Costas array for each size up to 31×31, but don't know any Costas array of size 32×32. Taken together, these claims imply that we know some of the Costas arrays of size 27×27 (say), but we don't know if we have found all of them yet. Michael Slone (talk) 01:44, 1 March 2008 (UTC)[reply]

Thanks for the quick reaction. I have red the article again and now have a much better understanding. Thanks. —Preceding unsigned comment added by 87.212.47.202 (talk) 18:17, 1 March 2008 (UTC)[reply]

Eponym?????

This article begins thus:

In mathematics, a Costas array can be regarded as....

It should say

In mathematics, a Costas array, named after ????? Costas, can be regarded as....

for the appropriate value of ?????. 05:24, 4 July 2008 (UTC)

John P. Costas, engineer active in the 1950s and 1960s. Unfortunately there is a CEO with the same name, so google is nearly useless. MathSciNet only has a single paper by him. http://www.costasarray.org/ is not terribly helpful for the biographical details. JackSchmidt (talk) 05:36, 4 July 2008 (UTC)[reply]

He's the John Costas who invented the Costas loop. There's some biographical data in a talk by Rickard [[1]] (who has interviewed Costas, so it's reasonably reliable) which I will use to make a page for him. Jhealy (talk) 12:51, 17 July 2008 (UTC).[reply]

Merger proposal

The article Welch-Costas array is very short and says little that is not already covered here. Richard Pinch (talk) 18:51, 17 August 2008 (UTC)[reply]

Done. Richard Pinch (talk) 21:10, 31 August 2008 (UTC)[reply]

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 All Costas arrays of size up to and including '''26x26''' are known.
 It is not known whether Costas arrays exist for all sizes. Currently, the smallest sizes for which no arrays are known are '''32x32 and 33x33.'''
-?? If I read this my conclusion would be that we know then up to 31x31. So why say whe know then up to 26x26. {{unsigned|87.212.47.202}}
+?? If I read this my conclusion would be that we know then up to 31x31. So why say whe know then up to 26x26. <small><span class="autosigned">—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:87.212.47.202|87.212.47.202]] ([[User talk:87.212.47.202|talk]] • [[Special:Contributions/87.212.47.202|contribs]]) </span></small><!-- Template:Unsigned -->
 :These statements are not in conflict.  The first statement says we have a ''complete list'' of Costas arrays of size 26×26 or smaller.  The second statement says we know ''at least one'' Costas array for each size up to 31×31, but don't know any Costas array of size 32×32.  Taken together, these claims imply that we know ''some'' of the Costas arrays of size 27×27 (say), but we don't know if we have found ''all'' of them yet. [[User:Michael Slone|Michael Slone]] ([[User talk:Michael Slone|talk]]) 01:44, 1 March 2008 (UTC)