This site is supported by donations to The OEIS Foundation.

 Annual appeal: Please make a donation to keep the OEIS running! Over 6000 articles have referenced us, often saying "we discovered this result with the help of the OEIS". Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A013516 Denominators in the Taylor expansion exp(cosec(x)-cot(x))=1 + x/2 + x^2/8 + x^3/16 + 3*x^4/128 + 37*x^5/3840 + 59*x^6/15360 + ... 1
 1, 2, 8, 16, 128, 3840, 15360, 92160, 1474560, 185794560, 3715891200, 117964800, 2831155200, 51011754393600, 13603134504960, 8569974738124800, 1371195958099968000, 46620662575398912000, 239763407530622976000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS The numerators are apparently the same as A047691. LINKS EXAMPLE exp(cosec(x)-cot(x)) = 1 +1*x/(2^1*1!) + 1*x^2/(2^2*2!) + 3*x^3/(2^3*3!) + 9*x^4/(2^4*4!) + 37*x^5/(2^5*5!) +  177*x^6/(2^6*6!) +959*x^7/(2^7*7!)+ ... MAPLE A013516 := proc(n)         exp(csc(x)-cot(x)) ;         coeftayl( %, x=0, n) ;         denom(%) ; end proc:  # R. J. Mathar, Dec 18 2011 CROSSREFS Cf. A006229, A002425 (expansion of cosec(x)-cot(x)). Sequence in context: A046161 A092978 A280777 * A259688 A101059 A191999 Adjacent sequences:  A013513 A013514 A013515 * A013517 A013518 A013519 KEYWORD nonn,frac AUTHOR Patrick Demichel (patrick.demichel(AT)hp.com) EXTENSIONS Corrected by R. J. Mathar, Dec 18 2011 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.