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

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A112119 G.f. A(x) satisfies A(A(A(..(A(x))..))) = B(x) (9th self-COMPOSE of A) such that the coefficients of B(x) consist only of numbers {1,2,3,..,9}, with B(0) = 0. 3

%I #6 Mar 12 2015 18:43:25

%S 1,1,-7,81,-1122,16906,-264109,4150081,-64119406,955386299,

%T -13491950523,178108552187,-2193288809125,25965294143459,

%U -320197330438145,4331428366450929,-54509980572007649,309687851858995853,8841175049606909354,-260481122023484957344,727627679068983588258

%N G.f. A(x) satisfies A(A(A(..(A(x))..))) = B(x) (9th self-COMPOSE of A) such that the coefficients of B(x) consist only of numbers {1,2,3,..,9}, with B(0) = 0.

%e A(x) = x + x^2 - 7*x^3 + 81*x^4 - 1122*x^5 + 16906*x^6 +...

%e where A(A(A(A(A(A(A(A(A(x))))))))) =

%e x + 9*x^2 + 9*x^3 + 9*x^4 + 6*x^5 + 6*x^6 + 3*x^7 +...

%e is the g.f. of A112118.

%o (PARI) {a(n,m=9)=local(F=x+x^2+x*O(x^n),G);if(n<1,0, for(k=3,n, G=F+x*O(x^k);for(i=1,m-1,G=subst(F,x,G)); F=F-((polcoeff(G,k)-1)\m)*x^k); return(polcoeff(F,n,x)))}

%Y Cf. A112118, A112104-A112117, A112120-A112127.

%K sign

%O 1,3

%A _Paul D. Hanna_, Aug 27 2005

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.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 19 19:02 EDT 2024. Contains 371798 sequences. (Running on oeis4.)