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.
%I A065923 #24 Aug 17 2017 06:13:21 %S A065923 1,-2,19,-287,6046,-163529,5402503,-210861146,9494154073, %T A065923 -484412718869,27621019129606,-1740608617884047,120129615653128849, %U A065923 -9011461782602547722,730048534006459494331,-63523233920344578554519,5908390803126052265064598 %N A065923 Bessel polynomial y_n(-3). %D A065923 J. Riordan, Combinatorial Identities, Wiley, 1968, p. 77. %H A065923 G. C. Greubel, <a href="/A065923/b065923.txt">Table of n, a(n) for n = 0..345</a> %H A065923 <a href="/index/Be#Bessel">Index entries for sequences related to Bessel functions or polynomials</a> %F A065923 a(n) = -(6*n-3)*a(n-1) + a(n-2) for n >= 2. - _Sergei N. Gladkovskii_, May 17 2013 %F A065923 G.f.: 1/Q(0), where Q(k)= 1 - x + 3*x*(k+1)/Q(k+1); (continued fraction). - _Sergei N. Gladkovskii_, May 17 2013 %F A065923 From _G. C. Greubel_, Aug 14 2017: (Start) %F A065923 a(n) = (1/2)_{n} * (-3)^n *hypergeometric1f1(-n; -2n; -2/3), where (a)_{n} is the Pochhammer symbol. %F A065923 E.g.f.: (1+6*x)^(-1/2) * exp((sqrt(1+6*x) - 1)/3). (End) %F A065923 G.f.: (1/(1-x))*hypergeometric2f0(1,1/2; - ; -6*x/(1-x)^2). - _G. C. Greubel_, Aug 16 2017 %p A065923 f:= gfun:-rectoproc({a(n)= -(6*n-3)*a(n-1) + a(n-2),a(0)=1,a(1)=-2},a(n),remember): %p A065923 map(f, [$0..50]); # _Robert Israel_, Aug 16 2017 %t A065923 Table[Pochhammer[1/2, n]*(-6)^n*Hypergeometric1F1[0 - n, -2*n, -2/3], {n, 0, 50}] (* _G. C. Greubel_, Aug 14 2017 *) %o A065923 (PARI) for(n=0,50, print1(sum(k=0,n, ((n+k)!/(k! * (n-k)!))*(-3/2)^k), ", ")) \\ _G. C. Greubel_, Aug 14 2017 %Y A065923 Polynomial coefficients are in A001498. %K A065923 sign %O A065923 0,2 %A A065923 _N. J. A. Sloane_, Dec 08 2001