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 A005212 n! if n is odd otherwise 0 (from the Taylor series for sin x). 8
 0, 1, 0, 6, 0, 120, 0, 5040, 0, 362880, 0, 39916800, 0, 6227020800, 0, 1307674368000, 0, 355687428096000, 0, 121645100408832000, 0, 51090942171709440000, 0, 25852016738884976640000, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 COMMENTS Normally sequences like this are not included, since with the alternating 0's deleted it is already in the database. From Michael Somos, Mar 04 2004: (Start) Stirling transform of a(n) = [1,0,6,0,120,0,5040,...] is A089677(n) = [1,1,7,37,271,...]. Stirling transform of a(n-1) = [0,1,0,6,0,120,0,...] is A000670(n-1) = [0,1,3,13,75,...]. Stirling transform of a(n-1) = [1,1,0,6,0,120,0,...] is A052856(n-1) = [1,2,4,14,76,...]. (End) REFERENCES D. R. Hofstadter, Fluid Concepts and Creative Analogies: Computer Models of the Fundamental Mechanisms of Thought, (together with the Fluid Analogies Research Group), NY: Basic Books, 1995. LINKS G. C. Greubel, Table of n, a(n) for n = 0..448 FORMULA E.g.f.: -log(cos(arcsin(x))). - Vladimir Kruchinin, Jun 15 2011 MAPLE BB:=[T, {T=Prod(Z, F), F=Sequence(B), B=Prod(Z, Z)}, labeled]: seq(count(BB, size=i), i=0..24); # Zerinvary Lajos, Apr 22 2007 MATHEMATICA nn = 20; Rest[ Range[0, nn]! CoefficientList[ Series[ Log[(1 - x^2)^(-1/2)], {x, 0, nn}], x]] (* Geoffrey Critzer, May 29 2013 *) Riffle[Range[1, 25, 2]!, 0, {1, -1, 2}] (* Harvey P. Dale, Mar 10 2017 *) PROG (PARI) a(n)=if(n<0, 0, if(n%2, n!, 0)); CROSSREFS Sequence in context: A085511 A187525 A187696 * A167028 A246137 A052679 Adjacent sequences:  A005209 A005210 A005211 * A005213 A005214 A005215 KEYWORD nonn AUTHOR STATUS approved

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Last modified March 23 12:43 EDT 2019. Contains 321430 sequences. (Running on oeis4.)