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A064644 - 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>A064644 - OEIS</title> <link rel="search" type="application/opensearchdescription+xml" title="OEIS" href="/oeis.xml"> <script> var myURL = "\/A064644" 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=%2fA064644">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="A064644 - 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> A064644 </div> <div class=seqname> Array defined in <a href="/A064643" title="Bidirectional 'Delannoy' variation of the Boustrophedon transform applied to all 1's sequence: Fill an triangular array in a...">A064643</a> read from left to right (cf. <a href="/A107783" title="Array defined in A064643 read in direction in which it was created.">A107783</a>). </div> </div> <div class=scorerefs> 2 </div> </div> <div> <div class=seqdatabox> <div class=seqdata>1, 2, 1, 1, 5, 6, 22, 21, 13, 1, 1, 45, 84, 104, 105, 631, 630, 562, 412, 211, 1, 1, 1263, 2500, 3558, 4285, 4602, 4603, 39469, 39468, 37573, 33180, 26560, 18305, 9207, 1, 1, 78939, 157243, 230496, 293794, 342944, 375058, 388869, 388870, 4327322</div> <div class=seqdatalinks> (<a href="/A064644/list">list</a>; <a href="/A064644/table">table</a>; <a href="/A064644/graph">graph</a>; <a href="/search?q=A064644+-id:A064644">refs</a>; <a href="/A064644/listen">listen</a>; <a href="/history?seq=A064644">history</a>; <a href="/search?q=id:A064644&fmt=text">text</a>; <a href="/A064644/internal">internal format</a>) </div> </div> </div> <div class=entry> <div class=section> <div class=sectname>OFFSET</div> <div class=sectbody> <div class=sectline>0,2</div> </div> </div> <div class=section> <div class=sectname>LINKS</div> <div class=sectbody> <div class=sectline><a href="/A064644/b064644.txt">Table of n, a(n) for n=0..45.</a></div> </div> </div> <div class=section> <div class=sectname>EXAMPLE</div> <div class=sectbody> <div class=sectline>1; 2,1; 1,5,6; 22,21,13,1; ...</div> </div> </div> <div class=section> <div class=sectname>CROSSREFS</div> <div class=sectbody> <div class=sectline>Sequence in context: <a href="/A092437" title="Triangle read by rows, arising from enumeration of domino tilings of Aztec Pillow-like regions.">A092437</a> <a href="/A064814" title="Greatest common divisor of n and the n-th composite number.">A064814</a> <a href="/A051012" title="Denominator of average of number of steps in Euclidean algorithm for all gcd(m,n) with 0 <= m < n.">A051012</a> * <a href="/A306444" title="A(n,k) = binomial((2*k+1)*n+2, k*n+1)/((2*k+1)*n+2), square array A(n,k) read by antidiagonals, for n >= 0, k >= 0.">A306444</a> <a href="/A090210" title="Triangle of certain generalized Bell numbers.">A090210</a> <a href="/A248925" title="Triangle in which row n consists of the coefficients in Sum_{m=0..n} x^m * Product_{k=m+1..n} (1-k*x), as read by rows.">A248925</a></div> <div class=sectline>Adjacent sequences: <a href="/A064641" title="Unidirectional 'Delannoy' variation of the Boustrophedon transform applied to all 1's sequence: construct an array in which ...">A064641</a> <a href="/A064642" title="Triangle defined in A064641 read by rows.">A064642</a> <a href="/A064643" title="Bidirectional 'Delannoy' variation of the Boustrophedon transform applied to all 1's sequence: Fill an triangular array in a...">A064643</a> * <a href="/A064645" title="Table where the entry (n,k) (n >= 0, k >= 0) gives number of Motzkin paths of the length n with the minimum peak width of k.">A064645</a> <a href="/A064646" title="Numerators of partial sums of reciprocals of primorial numbers.">A064646</a> <a href="/A064647" title="Denominators of partial sums of reciprocals of primorial numbers.">A064647</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>,<span title="typically a triangle of numbers, made into a sequence by reading it row by row"><a href="/A064644/table">tabl</a></span></div> </div> </div> <div class=section> <div class=sectname>AUTHOR</div> <div class=sectbody> <div class=sectline><a href="/wiki/User:Floor_van_Lamoen">Floor van Lamoen</a>, Oct 03 2001</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 April 11 00:44 EDT 2025. Contains 382682 sequences.</div> <div class=legal> <a href="/wiki/Legal_Documents">License Agreements, Terms of Use, Privacy Policy</a> </div> </div> </center> </div> </body> </html>