%I #11 Aug 14 2015 22:29:22
%S 9,0,0,2,9,-3,0,-8,2,0,25,-5,9,-12,-9,2,0,-49,49,-7,0,96,-40,-8,2,9,
%T -27,-135,78,-9,0,-150,355,-100,-5,2,0,242,-121,-242,110,-11,9,-48,
%U -828,892,-201,0,2,0,-338,1521,-507,-338,143,-13
%N Triangle read by rows: row n gives coefficients in an expansion of M_n*M_{-n}, where M_n = x^n+y^n+z^n and x,y,z satisfy x+y+z=0.
%C Rows lengths are 1,1,2,2,3,3,4,4,...
%D A. van Wijngaarden, On the coefficients of the modular invariant J(tau), Proceedings of the Koninklijke Nederlandse Akademie van Wetenschappen, Series A, 56 (1953), 389-400
%H A. van Wijngaarden, <a href="/A000521/a000521.pdf">On the coefficients of the modular invariant J(tau)</a>, Proceedings of the Koninklijke Nederlandse Akademie van Wetenschappen, Series A, 56 (1953), 389-400. [Annotated scanned copy]
%e Triangle begins:
%e 9,
%e 0,
%e 0,2,
%e 9,-3,
%e 0,-8,2,
%e 0,25,-5,
%e 9,-12,-9,2,
%e 0,-49,49,-7,
%e 0,96,-40,-8,2,
%e 9,-27,-135,78,-9,
%e 0,-150,355,-100,-5,2,
%e 0,242,-121,-242,110,-11,
%e 9,-48,-828,892,-201,0,2,
%e 0,-338,1521,-507,-338,143,-13,
%e ...
%K sign,tabf
%O 0,1
%A _N. J. A. Sloane_, Jun 24 2015