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A055350 - OEIS
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 3.2 Final//EN"> <html> <head> <link rel="stylesheet" href="/styles.css"> <meta name="format-detection" content="telephone=no"> <meta http-equiv="content-type" content="text/html; charset=utf-8"> <meta name=viewport content="width=device-width, initial-scale=1"> <meta name="keywords" content="OEIS,integer sequences,Sloane" /> <title>A055350 - OEIS</title> <link rel="search" type="application/opensearchdescription+xml" title="OEIS" href="/oeis.xml"> <script> var myURL = "\/A055350" function redir() { var host = document.location.hostname; if(host != "oeis.org" && host != "127.0.0.1" && !/^([0-9.]+)$/.test(host) && host != "localhost" && host != "localhost.localdomain") { document.location = "https"+":"+"//"+"oeis"+".org/" + myURL; } } function sf() { if(document.location.pathname == "/" && document.f) document.f.q.focus(); } </script> </head> <body bgcolor=#ffffff onload="redir();sf()"> <div class=loginbar> <div class=login> <a href="/login?redirect=%2fA055350">login</a> </div> </div> <div class=center><div class=top> <center> <div class=donors> The OEIS is supported by <a href="http://oeisf.org/#DONATE">the many generous donors to the OEIS Foundation</a>. </div> <div class=banner> <a href="/"><img class=banner border="0" width="600" src="/banner2021.jpg" alt="A055350 - OEIS"></a> </div> </center> </div></div> <div class=center><div class=pagebody> <div class=searchbarcenter> <form name=f action="/search" method="GET"> <div class=searchbargreet> <div class=searchbar> <div class=searchq> <input class=searchbox maxLength=1024 name=q value="" title="Search Query"> </div> <div class=searchsubmit> <input type=submit value="Search" name=go> </div> <div class=hints> <span class=hints><a href="/hints.html">Hints</a></span> </div> </div> <div class=searchgreet> (Greetings from <a href="/welcome">The On-Line Encyclopedia of Integer Sequences</a>!) </div> </div> </form> </div> <div class=sequence> <div class=space1></div> <div class=line></div> <div class=seqhead> <div class=seqnumname> <div class=seqnum> A055350 </div> <div class=seqname> Number of labeled mobiles (circular rooted trees) with n nodes and 3 leaves. </div> </div> <div class=scorerefs> 2 </div> </div> <div> <div class=seqdatabox> <div class=seqdata>8, 220, 4200, 71400, 1176000, 19474560, 330220800, 5787936000, 105380352000, 1997835840000, 39477236198400, 813155511168000, 17453093898240000, 390070546145280000, 9070029416448000000, 219204470936715264000</div> <div class=seqdatalinks> (<a href="/A055350/list">list</a>; <a href="/A055350/graph">graph</a>; <a href="/search?q=A055350+-id:A055350">refs</a>; <a href="/A055350/listen">listen</a>; <a href="/history?seq=A055350">history</a>; <a href="/search?q=id:A055350&fmt=text">text</a>; <a href="/A055350/internal">internal format</a>) </div> </div> </div> <div class=entry> <div class=section> <div class=sectname>OFFSET</div> <div class=sectbody> <div class=sectline>4,1</div> </div> </div> <div class=section> <div class=sectname>LINKS</div> <div class=sectbody> <div class=sectline>Georg Fischer, <a href="/A055350/b055350.txt">Table of n, a(n) for n = 4..250</a></div> <div class=sectline><a href="/index/Mo#mobiles">Index entries for sequences related to mobiles</a></div> </div> </div> <div class=section> <div class=sectname>MATHEMATICA</div> <div class=sectbody> <div class=sectline>m = 20;</div> <div class=sectline>L[x_] = Log[1-x] + O[x]^m // Normal;</div> <div class=sectline>A[_] = 0;</div> <div class=sectline>Do[A[x_] = x y - x L[A[x]] + O[x]^k // Normal // Expand, {k, m}];</div> <div class=sectline>Drop[(SeriesCoefficient[#, {y, 0, 3}]& /@ CoefficientList[A[x], x]) * Range[0, m-1]!, 4] (* <a href="/wiki/User:Jean-Fran莽ois_Alcover">Jean-Fran莽ois Alcover</a>, Nov 01 2019 *)</div> </div> </div> <div class=section> <div class=sectname>CROSSREFS</div> <div class=sectbody> <div class=sectline>Column 3 of <a href="/A055349" title="Triangle of labeled mobiles (circular rooted trees) with n nodes and k leaves.">A055349</a>.</div> <div class=sectline>Sequence in context: <a href="/A305517" title="Number of nXn 0..1 arrays with every element unequal to 0, 1, 2, 3, 4 or 5 king-move adjacent elements, with upper left elem...">A305517</a> <a href="/A298964" title="Number of n X n 0..1 arrays with every element equal to 0, 1, 2, 3, 4 or 5 king-move adjacent elements, with upper left elem...">A298964</a> <a href="/A298455" title="Number of n X n 0..1 arrays with every element equal to 2, 3, 4, 5 or 6 king-move adjacent elements, with upper left element...">A298455</a> * <a href="/A183261" title="Number of n X 6 binary arrays with the number of 0-1 adjacencies equal to the number of 0-0 adjacencies.">A183261</a> <a href="/A316954" title="Number of nXn 0..1 arrays with every element unequal to 0, 1, 2, 3, 4, 5 or 8 king-move adjacent elements, with upper left e...">A316954</a> <a href="/A299734" title="Number of n X n 0..1 arrays with every element equal to 0, 1, 2, 3, 4, 5 or 8 king-move adjacent elements, with upper left e...">A299734</a></div> <div class=sectline>Adjacent sequences: <a href="/A055347" title="Matrix inverse of triangle A055340(n+1,k).">A055347</a> <a href="/A055348" title="Column 1 of triangle A055347.">A055348</a> <a href="/A055349" title="Triangle of labeled mobiles (circular rooted trees) with n nodes and k leaves.">A055349</a> * <a href="/A055351" title="Number of labeled mobiles (circular rooted trees) with n nodes and 4 leaves.">A055351</a> <a href="/A055352" title="Number of labeled mobiles (circular rooted trees) with n nodes and 5 leaves.">A055352</a> <a href="/A055353" title="Number of labeled mobiles (circular rooted trees) with n nodes and 6 leaves.">A055353</a></div> </div> </div> <div class=section> <div class=sectname>KEYWORD</div> <div class=sectbody> <div class=sectline><span title="a sequence of nonnegative numbers">nonn</span></div> </div> </div> <div class=section> <div class=sectname>AUTHOR</div> <div class=sectbody> <div class=sectline><a href="/wiki/User:Christian_G._Bower">Christian G. Bower</a>, May 15 2000</div> </div> </div> <div class=section> <div class=sectname>STATUS</div> <div class=sectbody> <div class=sectline>approved</div> </div> </div> </div> <div class=space10></div> </div> </div></div> <p> <div class=footerpad></div> <div class=footer> <center> <div class=bottom> <div class=linksbar> <a href="/">Lookup</a> <a href="/wiki/Welcome"><font color="red">Welcome</font></a> <a href="/wiki/Main_Page"><font color="red">Wiki</font></a> <a href="/wiki/Special:RequestAccount">Register</a> <a href="/play.html">Music</a> <a href="/plot2.html">Plot 2</a> <a href="/demo1.html">Demos</a> <a href="/wiki/Index_to_OEIS">Index</a> <a href="/webcam">WebCam</a> <a href="/Submit.html">Contribute</a> <a href="/eishelp2.html">Format</a> <a href="/wiki/Style_Sheet">Style Sheet</a> <a href="/transforms.html">Transforms</a> <a href="/ol.html">Superseeker</a> <a href="/recent">Recents</a> </div> <div class=linksbar> <a href="/community.html">The OEIS Community</a> </div> <div class=linksbar> Maintained by <a href="http://oeisf.org">The OEIS Foundation Inc.</a> </div> <div class=dbinfo>Last modified March 13 19:40 EDT 2025. Contains 381739 sequences.</div> <div class=legal> <a href="/wiki/Legal_Documents">License Agreements, Terms of Use, Privacy Policy</a> </div> </div> </center> </div> </body> </html>