%I A119913
%S A119913 0,0,2,14,74,394,2344,16036,125628,1112028,10976118,119481218,
%T A119913 1421542550
%N A119913 Number of different simple cycles in the complete graph K_n; that is,
the number of subsets of at least 3 elements out of n, ordered up
to cyclic permutations.
%F A119913 a(n) = Sum_{k=3..n} (n choose k) * (k-1)! ; a(n) = Sum_{i=2..n-1}(Floor(e*i!))
- (n+3)(n-2)/2 ; a(n) = Sum_{k=1..n-1} A038154(k)
%F A119913 a(n) = 2*A002807(n). - Vladeta Jovovic (vladeta(AT)eunet.rs), Aug 04
2006
%e A119913 a(4)=14 because there are 6 4-cycles and 8 3-cycles.
%o A119913 Matlab: function a = an(n) s = 0; for i = 2:n-1 s = s+fix(exp(1)*factorial(i));
end a = s - (n+3)*(n-2)/2;
%Y A119913 Cf. A038154.
%Y A119913 Sequence in context: A095933 A043011 A138156 this_sequence A104871 A034573
A133224
%Y A119913 Adjacent sequences: A119910 A119911 A119912 this_sequence A119914 A119915
A119916
%K A119913 nonn
%O A119913 1,3
%A A119913 Amir M. Ben-Amram (amirben(AT)mta.ac.il), Aug 02 2006
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