to your HTML Add class="sortable" to any table you'd like to make sortable Click on the headers to sort Thanks to many, many people for contributions and suggestions. Licenced as X11: http://www.kryogenix.org/code/browser/licence.html This basically means: do what you want with it. */ var stIsIE = /*@cc_on!@*/false; sorttable = { init: function() { // quit if this function has already been called if (arguments.callee.done) return; // flag this function so we don't do the same thing twice arguments.callee.done = true; // kill the timer if (_timer) clearInterval(_timer); if (!document.createElement || !document.getElementsByTagName) return; sorttable.DATE_RE = /^(\d\d?)[\/\.-](\d\d?)[\/\.-]((\d\d)?\d\d)$/; forEach(document.getElementsByTagName('table'), function(table) { if (table.className.search(/\bsortable\b/) != -1) { sorttable.makeSortable(table); } }); }, makeSortable: function(table) { if (table.getElementsByTagName('thead').length == 0) { // table doesn't have a tHead. Since it should have, create one and // put the first table row in it. the = document.createElement('thead'); the.appendChild(table.rows[0]); table.insertBefore(the,table.firstChild); } // Safari doesn't support table.tHead, sigh if (table.tHead == null) table.tHead = table.getElementsByTagName('thead')[0]; if (table.tHead.rows.length != 1) return; // can't cope with two header rows // Sorttable v1 put rows with a class of "sortbottom" at the bottom (as // "total" rows, for example). This is B&R, since what you're supposed // to do is put them in a tfoot. So, if there are sortbottom rows, // for backwards compatibility, move them to tfoot (creating it if needed). sortbottomrows = []; for (var i=0; i
Longtime readers know we occasionally dabble in prime numbers and sometimes also history. That's why this super short Numberphile video leapt out at us in our YouTube feed, because it combines the two.
In the video, Brady Haran tracks down a copy of Marin Mersenne's 1644 book Cogitata Physico-Mathematica at the Royal Society, in which he listed the prime numbers associated with the formula 2n - 1, which have since become synonymous with his name. But, as Brady quickly identifies, Mersenne made a couple of mistakes in his published list. Here's the video:
If you would like to read Mersenne's book in the original Latin (or would like to read an English translation of it, Luke Welsh has got you covered!
Almost four centuries later, we know of just 52 Mersenne primes. When and where do you suppose they'll discover the next one?
Labels: math
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Closing values for previous trading day.
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