login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

a(n) = binomial(3+2*n, n) * binomial(8+2*n, 3+n).
1

%I #6 Jan 08 2020 00:30:52

%S 56,1050,16632,252252,3775200,56316546,840639800,12575971408,

%T 188663555808,2838687761000,42836302222560,648207031545000,

%U 9834444563299200,149569451148798450,2279905857066915000,34825702701626575200,532997250488883180000,8172044956118671828200

%N a(n) = binomial(3+2*n, n) * binomial(8+2*n, 3+n).

%H Andrew Howroyd, <a href="/A114059/b114059.txt">Table of n, a(n) for n = 0..200</a>

%F a(n) = A062190(3+2*n, 3+n).

%e a(0) = C(3+2*0,0)*C(8+2*0,3+0) = C(3,0)*C(8,3) = 1*56 = 56.

%e a(10) = C(3+2*10,10)*C(8+2*10,3+10) = C(23,10)*C(28,13) = 1144066*37442160 = 42836302222560.

%o (PARI) a(n)={binomial(3+2*n, n) * binomial(8+2*n, 3+n)} \\ _Andrew Howroyd_, Jan 07 2020

%Y Cf. A062190.

%K easy,nonn

%O 0,1

%A _Zerinvary Lajos_, Feb 02 2006

%E Name edited and terms a(11) and beyond from _Andrew Howroyd_, Jan 07 2020