A000110

[David Wilson]

1.  The comment

%C A000110 Bell(n) = (1/(n-1)!) * [ n^(n-1) + C(n-1,2)*(n-2)^(n-1) + 
2*C(n-1,3)*(n-3)^(n-1) + 9*C(n-1,4)*(n-4)^(n-1) + \
  44*C(n-1,5)*(n-5)^(n-1) + 265*C(n-1,6)*(n-6)^(n-1) + 
1854*C(n-1,7)*(n-7)^(n-1) + 14833*C(n-1,8)*(n-8)^(n-1) + 133496*\
  C(n-1,9)*(n-9)^(n-1) + 1334961*C(n-1,10)*(n-10)^(n-1) + ..... ]. - Andre 
F. Labossiere (sobal(AT)laposte.net), Dec 01\
   2004

can be replaced with the equivalent formula

%F a(n) = SUM(j = 0 to n-1, A000166(n) * C(n-1, j) * (n-j)^(n-1)) - Andre F. 
Labossiere (sobal(AT)laposte.net), Dec 01 2004

2.  You can add the comment

%C a(n-1) = number of nonisomorphic colorings of a map consisting of a row 
of n+1 adjacent regions. 



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