%I A002477 M5386 N2339
%S A002477 1,121,12321,1234321,123454321,12345654321,1234567654321,123456787654321,
%T A002477 12345678987654321,1234567900987654321,123456790120987654321,
%U A002477 12345679012320987654321,1234567901234320987654321
%N A002477 Wonderful Demlo numbers: a(n) = ((10^(n+1)-1)/9)^2 = A000042^2.
%D A002477 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, 
               Academic Press, 1995 (includes this sequence).
%D A002477 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 
               (includes this sequence).
%D A002477 D. R. Kaprekar, On Wonderful Demlo numbers, Math. Stud., 6 (1938), 68.
%H A002477 S. Plouffe, <a href="http://www.lacim.uqam.ca/%7Eplouffe/articles/MasterThesis.pdf">
               Approximations de S\'{e}ries G\'{e}n\'{e}ratrices et Quelques Conjectures</
               a>, Dissertation, Universit\'{e} du Qu\'{e}bec \`{a} Montr\'{e}al, 
               1992.
%H A002477 S. Plouffe, <a href="http://www.lacim.uqam.ca/%7Eplouffe/articles/FonctionsGeneratrices.pdf">
               1031 Generating Functions and Conjectures</a>, Universit\'{e} du 
               Qu\'{e}bec \`{a} Montr\'{e}al, 1992.
%H A002477 Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/
               DemloNumber.html">Link to a section of The World of Mathematics.</
               a>
%H A002477 Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/
               Repunit.html">Repunit</a>
%F A002477 G.f.: x*(1+10*x) / ((1-x)*(1-10*x)*(1-100*x)).
%F A002477 G.f.:sage: taylor( mul( x*(1+10*x) / ((1-x)*(1-10*x)*(1-100*x)) for i 
               in xrange(1,2)),x,0,23)# [From Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), 
               Jun 03 2009]
%p A002477 A002477:=-(1+10*z)/(z-1)/(100*z-1)/(10*z-1); [S. Plouffe in his 1992 
               dissertation.]
%t A002477 lst={};Do[p=((10^n-1)/9)^2;AppendTo[lst, p], {n, 0, 5!}];lst [From Vladimir 
               Orlovsky (4vladimir(AT)gmail.com), Sep 28 2008]
%o A002477 (Other) sage: [gaussian_binomial(n,1,10)^2 for n in xrange(1,14)] # [From 
               Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Jun 03 2009]
%Y A002477 Cf. A002275.
%Y A002477 Sequence in context: A137466 A062689 A057139 this_sequence A068117 A080162 
               A030174
%Y A002477 Adjacent sequences: A002474 A002475 A002476 this_sequence A002478 A002479 
               A002480
%K A002477 nonn,easy
%O A002477 1,2
%A A002477 N. J. A. Sloane (njas(AT)research.att.com).
%E A002477 Minor edits from N. J. A. Sloane (njas(AT)research.att.com), Aug 18 2009