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 A018927 For each permutation p of {1,2,...,n} define maxjump(p) = max(p(i) - i); a(n) is sum of maxjumps of all p. 4

%I

%S 0,1,7,45,313,2421,20833,198309,2073793,23664021,292834513,3907994949,

%T 55967406433,856355084661,13944569166193,240803714700069,

%U 4395998055854593,84596337986326101,1711691067680320273

%N For each permutation p of {1,2,...,n} define maxjump(p) = max(p(i) - i); a(n) is sum of maxjumps of all p.

%F a(n) = Sum_{k=0..n-1} k*k!*((k+1)^(n-k)-k^(n-k)).

%F a(n) = Sum_{k=0..n*(n-1)/2} k*A127452(n-1,k). - _Paul D. Hanna_, Jan 15 2007

%t Table[Sum[k*k!*((k+1)^(n-k)-k^(n-k)),{k,0,n-1}],{n,1,20}] (* _Vaclav Kotesovec_, Mar 17 2014 *)

%Y Cf. A127452, A130153.

%K nonn

%O 1,3

%A _Emeric Deutsch_

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