A156922 - OEIS

%I #2 Mar 30 2012 18:59:44

%S 1,15,129,877,5280,29658,159742,838038,4323003,22057825,111750519,

%T 563535483,2833221970,14216330916,71243079660,356731958812,

%U 1785306330981,8931761831331,44675371382365

%N Third right hand column (n-m=2) of the A156920 triangle

%F a(n) = 14*a(n-1)-75*a(n-2)+196*a(n-3)-263*a(n-4)+174*a(n-5)-45*a(n-6)

%F a(n) = (4*n^2-108*n*3^n+24*n-378*3^n+375*5^n+35)/32

%F G.f.: GF1(z;RHCnr=3) = (1+z-6*z^2)/((1-5*z)*(1-3*z)^2*(1-z)^3)

%Y Other columns A000340, A156923, A156924.

%Y Equals A156920 third right hand column.

%Y Equals A156919 third right hand column divided by 4.

%Y Equals A142963 third right hand column divided by 2^n.

%K easy,nonn

%O 0,2

%A _Johannes W. Meijer_, Feb 20 2009