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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A160623 Numerator of Laguerre(n, 2).

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%I A160623 #18 Feb 16 2025 08:33:10
%S A160623 1,-1,-1,-1,1,11,37,209,113,23,-4381,-84389,-310517,-4103887,
%T A160623 -25059901,-274436401,-13182829,-104362273,1748375381,690031209911,
%U A160623 4647089032189,112233351264271,1276100569319881,2131681036523177,71497025649480187,1365106755339875117
%N A160623 Numerator of Laguerre(n, 2).
%H A160623 Harvey P. Dale, <a href="/A160623/b160623.txt">Table of n, a(n) for n = 0..500</a>
%H A160623 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/LaguerrePolynomial.html">Laguerre Polynomial</a>
%H A160623 Wikipedia, <a href="https://en.wikipedia.org/wiki/Laguerre_polynomials">Laguerre polynomials</a>
%F A160623 Numerators of coefficients in expansion of exp(-2*x/(1 - x))/(1 - x). - _Ilya Gutkovskiy_, Aug 29 2018
%e A160623 1, -1, -1, -1/3, 1/3, 11/15, 37/45, 209/315, 113/315, 23/2835, -4381/14175, -84389/155925, -310517/467775, ... = A160623/A160624.
%t A160623 Numerator[LaguerreL[Range[0,30],2]] (* _Harvey P. Dale_, May 16 2012 *)
%o A160623 (PARI) for(n=0,30, print1(numerator(sum(k=0,n, binomial(n,k)*((-2)^k/k!))), ", ")) \\ _G. C. Greubel_, May 06 2018
%o A160623 (Magma) [Numerator((&+[Binomial(n,k)*((-2)^k/Factorial(k)): k in [0..n]])): n in [0..30]]; // _G. C. Greubel_, May 06 2018
%Y A160623 For denominators see A160624.
%Y A160623 Cf. A295382.
%K A160623 sign,frac
%O A160623 0,6
%A A160623 _N. J. A. Sloane_, Nov 14 2009