%I A061038
%S A061038 1,36,16,100,9,196,64,324,25,484,144,676,49,900,256,1156,81,1444,
%T A061038 400,1764,121,2116,576,2500,169,2916,784,3364,225,3844,1024,4356,
%U A061038 289,4900,1296,5476,361,6084,1600,6724,441,7396,1936,8100,529,8836
%N A061038 Denominator of 1/4 - 1/n^2.
%C A061038 a(4n)=(2n+1)^2=A016754, a(2n+1)=(4n+2)^2, n pos=A016826(n+1), a(4n+2)=(4n)^2, 
               n pos=A016802(n+1). J. J. Balmer, Notiz uber die Spectrallinien des 
               Wasserstoffs, Annalen der Physik (und Chemie) 25,(1885),80-85. First 
               text of two that year. Communicated June 25 1884 to the Naturforschende 
               Gesellschaft in Basel (where Euler was born). [From Paul Curtz (bpcrtz(AT)free.fr), 
               Oct 31 2008]
%H A061038 Harry J. Smith, <a href="b061038.txt">Table of n, a(n) for n=2,...,1000</
               a>
%F A061038 a(4n+2) = (2n+1)^2, a(2n+3) = (4n+6)^2, a(4n+4) = (4n+4)^2. - Ralf Stephan, 
               Jun 10 2005
%t A061038 Table[Denominator[1/4 - 1/n^2], {n, 2, 60}] - Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), 
               Apr 08 2006
%o A061038 (PARI) { for (n=2, 1000, write("b061038.txt", n, " ", denominator(1/4 
               - 1/n^2)) ) } [From Harry J. Smith (hjsmithh(AT)sbcglobal.net), Jul 
               17 2009]
%Y A061038 See A061037 for comments, references, links.
%Y A061038 Cf. A126252.
%Y A061038 Sequence in context: A066583 A073405 A056770 this_sequence A058231 A008894 
               A033973
%Y A061038 Adjacent sequences: A061035 A061036 A061037 this_sequence A061039 A061040 
               A061041
%K A061038 nonn,frac,nice
%O A061038 2,2
%A A061038 N. J. A. Sloane (njas(AT)research.att.com), May 26 2001
%E A061038 More terms from Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), 
               Apr 08 2006