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”).

Fourth (unsigned) column sequence of coefficient triangle A062137 of generalized Laguerre polynomials n!*L(n,3,x).
2

%I #28 Aug 09 2022 02:29:26

%S 1,28,560,10080,176400,3104640,55883520,1037836800,19978358400,

%T 399567168000,8310997094400,179819755315200,4045944494592000,

%U 94612855873536000,2297740785500160000,57903067794604032000

%N Fourth (unsigned) column sequence of coefficient triangle A062137 of generalized Laguerre polynomials n!*L(n,3,x).

%H Indranil Ghosh, <a href="/A062142/b062142.txt">Table of n, a(n) for n = 0..400</a>

%H <a href="/index/La#Laguerre">Index entries for sequences related to Laguerre polynomials</a>

%F a(n) = (n+3)!*binomial(n+6, 6)/3!; e.g.f.: (1 + 18*x + 45*x^2 + 20*x^3)/(1-x)^10.

%F If we define f(n,i,x) = Sum_{k=1..n} Sum_{j=1..k} binomial(k,j)*Stirling1(n,k)*Stirling2(j,i)*x^(k-j), then a(n-3) = (-1)^(n-1)*f(n,3,-7), (n>=3). - _Milan Janjic_, Mar 01 2009

%e a(3) = (3+3)!*binomial(3+6,6)/3! = (720*84)/6 = 10080. - _Indranil Ghosh_, Feb 23 2017

%t Table[(n+3)!*Binomial[n+6,6]/3!,{n,0,15}] (* _Indranil Ghosh_, Feb 23 2017 *)

%o (Sage) [binomial(n,6)*factorial(n-3)/factorial(3) for n in range(6, 22)] # _Zerinvary Lajos_, Jul 07 2009

%o (PARI) a(n) =(n+3)!*binomial(n+6,6)/3! \\ _Indranil Ghosh_, Feb 23 2017

%o (Python)

%o import math

%o f=math.factorial

%o def C(n,r):

%o return f(n)/f(r)/f(n-r)

%o def A062142(n):return f(n+3)*C(n+6,6)/f(3) # _Indranil Ghosh_, Feb 23 2017

%o (Magma) [Factorial(n+3)*Binomial(n+6,6)/6: n in [0..20]]; // _G. C. Greubel_, May 12 2018

%Y Cf. A062137, A062141.

%K nonn,easy

%O 0,2

%A _Wolfdieter Lang_, Jun 19 2001