Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.
%I #9 Sep 17 2017 22:13:31
%S 0,0,0,0,0,1,1,2,0,1,2,2,0,15,23,39,0,105,183,322,0,1016,1848,3347,0,
%T 10968,19943,36549,0,123086,227037,420857,0,1449771,2700611,5036699,0,
%U 17641455,33106802,62213791,0,220663135,416387896,786930971,0,2821102744
%N Number of solutions to 1 +- 5 +- 12 +- ... +- n*(3*n-1)/2 = 0.
%F a(n) = A292474(n)/2.
%Y Cf. A000326, A058498, A083527, A292474.
%K nonn
%O 1,8
%A _Seiichi Manyama_, Sep 17 2017