A004211, Bell numbers & StirlingS2

[Wouter Meeussen]

EIS holds:

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%I A004211 M2900
%S A004211 1,1,3,11,49,257,1539,10299,75905,609441,5284451,49134923,487026929,
%T A004211 5120905441,56878092067,664920021819,8155340557697,104652541401025,
%U A004211 1401572711758403,19546873773314571,283314887789276721
%N A004211 Coincides with its 2nd order binomial transform.
%H A004211 Transforms
%R A004211 DM 21 320 1978. EIS Section 2.7.
%O A004211 0,3
%F A004211 Expansion of exp(sinh(x).exp(x)). Lgd.e.g.f. = e^(2x).
%A A004211 njas
%K A004211 nonn,easy,nice

a %T line could read :
Table[Sum[StirlingS2[n,k] 2^(-k+n),{k,n}],{n,16}]

{1,3,11,49,257,1539,10299,75905,609441,5284451,49134923,487026929,5120905441,
  56878092067,664920021819,8155340557697}

If we change the "2^(-k+n)" to  "1"  then we get the Bell numbers.

neat linking eh?

wouter.
Dr. Wouter L. J. MEEUSSEN
w.meeussen.vdmcc at vandemoortele.be
eu000949 at pophost.eunet.be



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