%I A056992
%S A056992 1,4,9,7,7,9,4,1,9,1,4,9,7,7,9,4,1,9,1,4,9,7,7,9,4,1,9,1,4,9,7,7,9,4,1,
%T A056992 9,1,4,9,7,7,9,4,1,9,1,4,9,7,7,9,4,1,9,1,4,9,7,7,9,4,1,9,1,4,9,7,7,9,4,
%U A056992 1,9,1,4,9,7,7,9,4,1,9,1,4,9,7,7,9,4,1,9,1,4,9,7,7,9,4,1,9,1,4,9
%N A056992 Digital roots of square numbers A000290.
%C A056992 a(n) is also the decimal expansion of 499264730/333333333 [From Barbarel 
               Tres Mil (barbarel3000(AT)yahoo.es), Jul 28 2009]
%H A056992 Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/
               SquareNumber.html">Link to a section of The World of Mathematics.</
               a>
%F A056992 Cyclic with a period of nine. Note that (7, 9, 4, 1, 9, 1, 4, 9, 7) is 
               palindromic.
%F A056992 a(n)=(1/108)*{113*(n mod 9)-79*[(n+1) mod 9]+53*[(n+2) mod 9]+77*[(n+3) 
               mod 9]-7*[(n+4) mod 9]+17*[(n+5) mod 9]+41*[(n+6) mod 9]-43*[(n+7) 
               mod 9]-19*[(n+8) mod 9]}, with n>=0 [From Paolo P. Lava (ppl(AT)spl.at), 
               Aug 04 2009]
%F A056992 a(n)=3(1+cos(2n*pi/3)+ cos(4n*pi/3))+mod(3n^4+3n^6+4n^8,9) [From Ant 
               King (mathstutoring(AT)ntlworld.com), Oct 07 2009]
%F A056992 GF: x (1+4x+9x^2+7x^3+7x^4+9x^5+4x^6+x^7+9x^8)/((1-x)(1+x+x^2)(1+x^3+x^6)) 
               [From Ant King (mathstutoring(AT)ntlworld.com), Oct 20 2009]
%Y A056992 Cf. A000290, A056991.
%Y A056992 Sequence in context: A018880 A166923 A021205 this_sequence A004159 A092554 
               A155787
%Y A056992 Adjacent sequences: A056989 A056990 A056991 this_sequence A056993 A056994 
               A056995
%K A056992 nonn,base
%O A056992 1,2
%A A056992 Eric Weisstein (eric(AT)weisstein.com)