This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A122551 Denominators of the coefficients of the series for InverseErf(x). 2
 2, 24, 960, 80640, 11612160, 2554675200, 797058662400, 334764638208000, 182111963185152000, 124564582818643968000, 104634249567660933120000, 105889860562472864317440000, 127067832674967437180928000000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 COMMENTS Note: the term in x^11 in the series expansion above has a common factor of 7 between the numerator and denominator and is usually written 34807/364953600. The common factor of 7 occurs at n=6, 9, 12, etc. The sequence of the coefficients can be generated by combining this series with A002067. LINKS G. C. Greubel, Table of n, a(n) for n = 0..210 FORMULA a(n) = (2*n+1)!*2^(n+1). EXAMPLE InverseErf(x) = (1/2*sqrt(Pi))*x + (1/24*Pi^(3/2))*x^3 + (7/960*Pi^(5/2))*x^5 + (127/80640*Pi^(7/2))*x^7 + (4369/11612160*Pi^(9/2))*x^9 + (243649/2554675200*Pi^(11/2))*x^11 + ... MAPLE denominators:=[seq((2*n+1)!*2^(n+1), n=0..14)]; a:=proc(n) if(n < 2) then RETURN(1) fi; sum('binomial(2*n, 2*k)*a(k)*a(n-k-1)', 'k'=0..n-1); end; numerators:=[seq(a(n), n=0..14)]; MATHEMATICA Table[(2*n + 1)!*2^(n + 1), {n, 0, 25}] (* G. C. Greubel, Mar 19 2017 *) PROG (PARI) for(n=0, 25, print1((2*n+1)!*2^(n+1), ", ")) \\ G. C. Greubel, Mar 19 2017 CROSSREFS Cf. A002067 and A092676. Sequence in context: A015212 A012228 A062029 * A136524 A213984 A268311 Adjacent sequences:  A122548 A122549 A122550 * A122552 A122553 A122554 KEYWORD easy,nonn AUTHOR Marcus Blackburn (marcus.blackburn(AT)dial.pipex.com), Sep 20 2006 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
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified February 19 16:02 EST 2019. Contains 320311 sequences. (Running on oeis4.)