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%I #16 May 15 2024 03:59:04
%S 1,3,10,49,301,2161,17641,161281,1632961,18144001,219542401,
%T 2874009601,40475635201,610248038401,9807557760001,167382319104001,
%U 3023343138816001,57621363351552001,1155628453883904001,24329020081766400001
%N a(n) = floor(n*n!/2 + 1).
%C Concatenate all the permutations of 1..n in lexicographical order. a(n) is the number of ascending runs. [_David Scambler_, May 26 2011]
%F a(n) = A074143(n) + 1 for n >= 2. - _Georg Fischer_, May 15 2024
%p seq(floor(n*n!/2 + 1), n=1..20);
%Y Cf. A074143.
%K nonn,easy
%O 1,2
%A _Benoit Cloitre_, Apr 24 2003
%E Definition corrected by _Georg Fischer_, May 15 2024