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%I M5195 N2259 #25 Jan 01 2023 12:35:59
%S 1,27,511,8624,140889,2310945,38759930,671189310,12061579816,
%T 225525484184,4392554369840,89142436976320,1884434077831824,
%U 41471340993035856,949385215397800224,22587683825903611680,557978742043520648256,14297219701868137003200
%N Generalized Stirling numbers.
%C The asymptotic expansion of the higher order exponential integral E(x,m=6,n=2) ~ exp(-x)/x^6*(1 - 27/x + 511/x^2 - 8624/x^3 + 140889/x^4 - ...) leads to the sequence given above. See A163931 for E(x,m,n) information and A163932 for a Maple procedure for the asymptotic expansion. - _Johannes W. Meijer_, Oct 20 2009
%D N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H T. D. Noe, <a href="/A001709/b001709.txt">Table of n, a(n) for n = 0..100</a>
%H D. S. Mitrinovic and M. S. Mitrinovic, <a href="http://pefmath2.etf.rs/files/47/77.pdf">Tableaux d'une classe de nombres reliés aux nombres de Stirling</a>, Univ. Beograd. Publ. Elektrotehn. Fak. Ser. Mat. Fiz. No. 77 (1962), 1-77.
%H Robert E. Moritz, <a href="/A001701/a001701.pdf">On the sum of products of n consecutive integers</a>, Univ. Washington Publications in Math., 1 (No. 3, 1926), 44-49 [Annotated scanned copy]
%F a(n) = Sum_{k=0..n} (-1)^(n+k)*binomial(k+5, 5)*2^k*Stirling1(n+5, k+5). - Borislav Crstici (bcrstici(AT)etv.utt.ro), Jan 26 2004
%F E.g.f.: (6-120*log(1-x)+465*log(1-x)^2-580*log(1-x)^3+261*log(1-x)^4-36*log(1-x)^5)/(6*(1-x)^7). - _Vladeta Jovovic_, Mar 01 2004
%F If we define f(n,i,a)=sum(binomial(n,k)*stirling1(n-k,i)*product(-a-j,j=0..k-1),k=0..n-i), then a(n-5) = |f(n,5,2)|, for n>=5. [From _Milan Janjic_, Dec 21 2008]
%t nn = 25; t = Range[0, nn]! CoefficientList[Series[-Log[1 - x]^5/(120*(1 - x)^2), {x, 0, nn}], x]; Drop[t, 5] (* _T. D. Noe_, Aug 09 2012 *)
%o (PARI) a(n) = sum(k=0, n, (-1)^(n+k)*binomial(k+5, 5)*2^k*stirling(n+5, k+5, 1)); \\ _Michel Marcus_, Jan 01 2023
%K nonn
%O 0,2
%A _N. J. A. Sloane_
%E More terms from Borislav Crstici (bcrstici(AT)etv.utt.ro), Jan 26 2004
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