A049608 a(n)=T(n,n+2), array T as in A049600.

0, 1, 6, 34, 190, 1059, 5908, 33028, 185076, 1039525, 5851626, 33006438, 186519138, 1055789511, 5985405000, 33979107336, 193143097288

Offset: 0

Author

Clark Kimberling

Keywords

• nonn

Links

• Milan Janjic, Two Enumerative Functions

Formula

Conjecture: (n-1)*(2*n-1)*(n+2)*a(n) -12*n*(n-1)*(n+1)*a(n-1) +(n-2)*(2*n+1)*(n+1)*a(n-2)=0. - R. J. Mathar, Oct 26 2015