%I A001688 M4636 N1980
%S A001688 1,9,53,362,2790,24024,229080,2399760,27422640,339696000,4536362880,
%T A001688 64988179200,994447238400,16190733081600,279499828608000,5100017213491200,
%U A001688 98087346669312000,1983334021853184000,42063950934061056000,933754193111900160000
%N A001688 4th differences of factorial numbers.
%D A001688 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, 
               Academic Press, 1995 (includes this sequence).
%D A001688 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 
               (includes this sequence).
%D A001688 A. van Heemert, Cyclic permutations with sequences and related problems, 
               J. Reine Angew. Math., 198 (1957), 56-72.
%H A001688 Milan Janjic, <a href="http://www.pmfbl.org/janjic/">Enumerative Formulas 
               for Some Functions on Finite Sets</a>
%H A001688 <a href="Sindx_Fa.html#factorial">Index entries for sequences related 
               to factorial numbers</a>
%F A001688 For n>=0 a(n)=n!*(n^4 + 6*n^3 + 17*n^2 + 20*n + 9) - Benoit Cloitre (benoit7848c(AT)orange.fr), 
               Jun 10 2004
%o A001688 (PARI) a(n)=if(n<0,1,n!*(n^4 + 6*n^3 + 17*n^2 + 20*n + 9))
%Y A001688 Sequence in context: A005025 A038761 A003698 this_sequence A144040 A052108 
               A093846
%Y A001688 Adjacent sequences: A001685 A001686 A001687 this_sequence A001689 A001690 
               A001691
%K A001688 nonn
%O A001688 -1,2
%A A001688 N. J. A. Sloane (njas(AT)research.att.com).