The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation. Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A180515 E.g.f. A(x) satisfies A''(x)=2*A(x)^3+x*A(x)+1. 0
 0, 0, 1, 0, 0, 3, 0, 0, 198, 0, 0, 15390, 0, 0, 4611168, 0, 0, 1829539224, 0, 0, 1492247906784, 0, 0, 1669958449339824 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,6 COMMENTS The exponential generating function A(x) = x^2/+x^5/40 +11*x^8/2240+... satisfies the Painlevé II equation  A''(x) = 2*A(x)^3+x*A(x)+1. This is the case b=1 of the more general A''(x) = 2*A(x)^3+x*A(x)+b which has a solution a(0)=a(1)=0, a(2)=b/2, a(3)=a(4)=0 and, for n>4, a(n) = (2*A(n-2,3)+a(n-3)) / (n*(n-1)) where A(n,1)=a(n) and the components of A(n,k) with k>1 are recursively A(n,k) = sum_{i=0..n-k} a(i+1)*A(n-i-1,k-1). LINKS CROSSREFS Sequence in context: A160537 A215516 A009133 * A009138 A175562 A319330 Adjacent sequences:  A180512 A180513 A180514 * A180516 A180517 A180518 KEYWORD nonn AUTHOR Vladimir Kruchinin, Jan 21 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
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified January 28 03:34 EST 2020. Contains 331315 sequences. (Running on oeis4.)