The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A065946 Bessel polynomial {y_n}''(-2). 1
 0, 0, 6, -150, 3870, -110670, 3538500, -125941284, 4953759300, -213744815460, 10047637214010, -511403305348650, 28029852267603186, -1646397200571955650, 103190849406195456360, -6875135229835376875560, 485256294032090950981800 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 REFERENCES J. Riordan, Combinatorial Identities, Wiley, 1968, p. 77. LINKS G. C. Greubel, Table of n, a(n) for n = 0..360 FORMULA From G. C. Greubel, Aug 14 2017: (Start) a(n) = 4*n*(n - 1)*(1/2)_{n}*(-4)^(n - 2)*hypergeometric1f1[(2-n, -2*n, -1), where (a)_{n} is the Pochhammer symbol. E.g.f.: (1/16)*(1 + 4*x)^(-5/2)*((24*x^2 + 20*x + 2)*sqrt(1 + 4*x) + (16*x^3 - 12*x^2 - 24*x - 2))*exp((sqrt(1 + 4*x) -1)/2). (End) G.f.: (6*x^2/(1-x)^5)*hypergeometric2f0(3,5/2; - ; -4*x/(1-x)^2). - G. C. Greubel, Aug 16 2017 MATHEMATICA Join[{0, 0}, Table[4*n*(n - 1)*Pochhammer[1/2, n]*(-4)^(n - 2)* Hypergeometric1F1[2 - n, -2*n, -1], {n, 2, 50}]] (* G. C. Greubel, Aug 14 2017 *) PROG (PARI) for(n=0, 50, print1(sum(k=0, n-2, ((n+k+2)!/(4*k!*(n-k-2)!))*(-1)^k), ", ")) \\ G. C. Greubel, Aug 14 2017 CROSSREFS Cf. A001518, A001516. Sequence in context: A070025 A291110 A246214 * A222051 A285747 A013296 Adjacent sequences:  A065943 A065944 A065945 * A065947 A065948 A065949 KEYWORD sign AUTHOR N. J. A. Sloane, Dec 08 2001 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified January 18 15:09 EST 2022. Contains 350455 sequences. (Running on oeis4.)