OFFSET
0,3
FORMULA
Sum_{n>=0} a(n)*x^n/n!^2 = BesselI(0,2*sqrt(x/(1+x)))/(1+x).
a(n) = -3*(n-1)*n*a(n-1) - 3*(n-1)^4*a(n-2) - (n-2)^3*(n-1)^3*a(n-3). - Vaclav Kotesovec, Jun 08 2019
MATHEMATICA
Table[Sum[(-1)^(n - k)*(n!/k!)^2*Binomial[n, k], {k, 0, n}], {n, 0, 16}] (* Stefan Steinerberger, Jun 17 2007 *)
CROSSREFS
KEYWORD
easy,sign
AUTHOR
Vladeta Jovovic, Jul 25 2006
EXTENSIONS
More terms from Stefan Steinerberger, Jun 17 2007
STATUS
approved