A025260 - OEIS

%I #5 Feb 25 2015 14:53:05

%S 2,-2,1,2,2,1,2,10,26,44,68,149,398,938,1918,3916,8892,21258,49028,

%T 108580,242132,558456,1306824,3026445,6938518,15984346,37243510,

%U 87188492,203625452,474753470,1110012828,2606486124,6132979116,14430908200,33968899384

%N a(n) = a(1)*a(n-1) + a(2)*a(n-2) + ...+ a(n-3)*a(3) for n >= 4.

%F Conjecture: n*a(n) +2*(-2*n+3)*a(n-1) +8*(n-3)*a(n-2) +6*(-2*n+9)*a(n-3) +4*(n-6)*a(n-4)=0. - _R. J. Mathar_, Feb 25 2015

%K sign

%O 1,1

%A _Clark Kimberling_