%I A006595 M1794
%S A006595 1,2,7,33,192,1320,10440,93240,927360,10160640,121564800,
%T A006595 1576713600,22034073600,330032102400,5274286617600,89575694208000,
%U A006595 1611054821376000,30589118816256000,611426688897024000
%N A006595 (n+2)!/4 + n!/2.
%D A006595 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, 
               Academic Press, 1995 (includes this sequence).
%D A006595 L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 258.
%D A006595 J. R. Stembridge, Some combinatorial aspects of reduced words in finite 
               Coxeter groups. Trans. Amer. Math. Soc. 349 (1997), no. 4, 1285-1332.
%Y A006595 A diagonal of A059418.
%Y A006595 Sequence in context: A162661 A104981 A058797 this_sequence A059099 A020103 
               A014623
%Y A006595 Adjacent sequences: A006592 A006593 A006594 this_sequence A006596 A006597 
               A006598
%K A006595 nonn,easy
%O A006595 0,2
%A A006595 N. J. A. Sloane (njas(AT)research.att.com).
%E A006595 Improved description and sequence extended, 8/95.