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Number of solutions to +- 1^3 +- 3^3 +- 5^3 +- 7^3 +- ... +- (4*n-1)^3 = 0.
1

%I #19 Sep 19 2017 04:58:08

%S 1,0,0,0,0,0,0,0,2,6,2,10,118,88,254,3308,2558,9578,84568,121804,

%T 496396,3312400,5755724,19021024,116780256,241754350,883730786,

%U 4923089216,11668601596,42357336066,205859270250,538878582526,1974181071852,9194146886086,26277093562150

%N Number of solutions to +- 1^3 +- 3^3 +- 5^3 +- 7^3 +- ... +- (4*n-1)^3 = 0.

%F Constant term in the expansion of Product_{k=1..2*n} (x^((2*k-1)^3)+1/x^((2*k-1)^3)).

%e For n=8 the 2 solutions are

%e +1^3-3^3-5^3+7^3-9^3+11^3+13^3-15^3-17^3+19^3+21^3-23^3+25^3-27^3-29^3+31^3 = 0 and

%e -1^3+3^3+5^3-7^3+9^3-11^3-13^3+15^3+17^3-19^3-21^3+23^3-25^3+27^3+29^3-31^3 = 0.

%Y Cf. A158118, A292476, A292496.

%K nonn

%O 0,9

%A _Seiichi Manyama_, Sep 18 2017

%E a(29)-a(34) from _Alois P. Heinz_, Sep 18 2017