document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1198089>Question 1198089</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Show that the terms of the series ∑n r=1 log 5r are in AP. Hence, find the sum of the first twenty terms of the series and also the least value of n for which the sum to n terms exceeds 400.[ans: S20 = 146.78, n = 34] </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #831627 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=831627\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "It is not at all clear from your post what the sequence is. It looks like <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sum%28log%28%285r%29%29%2C1%2Cn%29 ALIGN=MIDDLE  ALT=\"sum%28log%28%285r%29%29%2C1%2Cn%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "With any interpretation I can see for the sequence, we always end up with a logarithmic sequence; but no such sequence is an AP, so the problem doesn't make sense.<br><BR>\n" );
document.write( "Re-post, making the question clear.<br><BR>\n" );
document.write( " </SPAN>\n" );
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