The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 56th year, we are closing in on 350,000 sequences, and we’ve crossed 9,700 citations (which often say “discovered thanks to the OEIS”).

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A116400 E.g.f. Bessel_I(2,2x)+Bessel_I(3,2x)+Bessel_I(4,2x). 0
 0, 0, 1, 1, 5, 5, 21, 21, 84, 84, 330, 330, 1287, 1287, 5005, 5005, 19448, 19448, 75582, 75582, 293930, 293930, 1144066, 1144066, 4457400, 4457400, 17383860, 17383860, 67863915, 67863915, 265182525 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,5 COMMENTS T(n,2) in number triangle A116399. Double of A002054. LINKS FORMULA G.f.: (1+x)*x^2*c(x^2)^4/(2-c(x^2)), c(x) the g.f. of A000108; a(n)=C(n+1,n/2-1)(1+(-1)^n)/2 + C(n,(n-1)/2-1)(1-(-1)^n)/2. PROG (PARI) a(n)=n=n\2; binomial(2*n+1, n-1) CROSSREFS A002054(n)=a(2n)=a(2n+1). Sequence in context: A171219 A325893 A146043 * A279810 A279750 A052992 Adjacent sequences:  A116397 A116398 A116399 * A116401 A116402 A116403 KEYWORD easy,nonn AUTHOR Paul Barry, Feb 13 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 December 1 01:37 EST 2021. Contains 349426 sequences. (Running on oeis4.)