document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=622974>Question 622974</A>: <I><SPAN STYLE=\"word-break: break-all;\"> conjecture a formula for the sequence.\r<BR>\n" );
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document.write( "3, 5, 11, 21, 43, 85, 171, 341, 683, 1365 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #391873 by </B><A HREF=/tutors/aboutme.mpl?userid=math-vortex><B>math-vortex(648)</B></A><img src=\"/images/stars/stars-11.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=math-vortex><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=math-vortex><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=391873\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Hi, there--<BR>\n" );
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document.write( "These look like Jacobsthal numbers, except that that sequence starts with 0, 1, 1, 3, 5, 11, ...<BR>\n" );
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document.write( "This sequence is similar to the Fibonacci sequence. Each number is the sequence is found by adding the number preceding it to twice the number before that.<BR>\n" );
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document.write( "For example, in your sequence<BR>\n" );
document.write( "11 is 5 plus two times 3.<BR>\n" );
document.write( "21 is 11 plus two times 5.<BR>\n" );
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document.write( "Here's a wikipedia link: http://en.wikipedia.org/wiki/Jacobsthal_number <BR>\n" );
document.write( "You can also google Jacobsthal numbers and find all sorts of cool stuff. Hope this helps.<BR>\n" );
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document.write( "Ms.Figgy<BR>\n" );
document.write( "math.in.the.vortex@gmail.com </SPAN>\n" );
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