The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A086894 a(n) = (A000522(2*n) + 1)/2. 1
 1, 3, 33, 979, 54801, 4932051, 651030673, 118487582403, 28437019776609, 8701728051642211, 3306656659624040001, 1527675376746306480243, 843276807963961177093873, 548129925176574765111017139, 414386223433490522423928956721, 360516014387136754508818192346851 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS Andrew Howroyd, Table of n, a(n) for n = 0..100 FORMULA a(n) = (1 + (2*n)!*Sum_{k=0..2*n} 1/k!)/2. - Andrew Howroyd, Jan 05 2020 PROG (PARI) a(n)={(1 + sum(k=0, 2*n, (2*n)!/k!))/2} \\ Andrew Howroyd, Jan 05 2020 CROSSREFS Cf. A000522. Sequence in context: A126466 A002112 A055549 * A255930 A255883 A215948 Adjacent sequences: A086891 A086892 A086893 * A086895 A086896 A086897 KEYWORD nonn AUTHOR Vladeta Jovovic, Aug 22 2003 EXTENSIONS Terms a(11) and beyond from Andrew Howroyd, Jan 05 2020 STATUS approved

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

Last modified August 7 05:36 EDT 2024. Contains 375008 sequences. (Running on oeis4.)