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%I A108563
%S A108563 0,0,2,2,0,4,0,0,2,0,0,4,2,0,4,0,0,0,2,0,4,4,0,0,0,0,0,2,0,4,4,0,2,0,0,
%T A108563 8,0,0,0,0,0,0,0,0,4,4,0,0,2,0,6,0,0,4,0,0,4,0,0,4,0,0,4,0,0,0,4,0,0,0,
%U A108563 0,0,2,0,0,6,0,8,0,0,4,0,0,4,4,0,0,0,0,0,0,0,0,4,0,0,0,0,6,4,0,4
%N A108563 Number of representations of n as sum of twice a square plus thrice a 
               square.
%H A108563 A. Berkovich and H. Yesilyurt, <a href="http://arXiv.org/abs/math.NT/
               0611300">Ramanujan's identities and representation of integers by 
               certain binary and quaternary quadratic forms</a>
%F A108563 G.f.: 1 + Sum_{k>0} x^k(1+x^(4k))(1+x^(6k))/(1+x^(12k)) - Sum_{k>0} kronecker(k,
               3)*x^k(1-x^(2k))/(1+x^(4k))
%F A108563 Expansion of phi(q^2)phi(q^3) where phi() is a Ramanujan theta function.
%o A108563 (PARI) for(n=0,120,print1(if(n<1,0,qfrep([2,0;0,3],n)[n]*2),","))
%Y A108563 Cf. a(n) = A000377(n) - A115660(n).
%Y A108563 Sequence in context: A011137 A143396 A090657 this_sequence A138476 A131381 
               A112080
%Y A108563 Adjacent sequences: A108560 A108561 A108562 this_sequence A108564 A108565 
               A108566
%K A108563 nonn
%O A108563 0,3
%A A108563 Ralf Stephan, May 13 2007
%E A108563 Edited by Charles R Greathouse IV (charles.greathouse(AT)case.edu), Oct 
               28 2009

    
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Last modified December 8 08:31 EST 2009. Contains 170430 sequences.


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