OFFSET
0,3
FORMULA
E.g.f.: A(x) = (1/x)*Series_Reversion(x/D(x)) where D(x) is the e.g.f. of A141358.
E.g.f.: A(x) = B(x*A(x)^3) where B(x) = exp(x*B(x)*exp(x^2*B(x)^2*exp(x^3*B(x)^3*exp(...)))) is the e.g.f. of A141356 = [1,1,3,22,245,3516,63727,1405384,...].
E.g.f.: A(x) = C(x*A(x)^2) where C(x) = exp(x*C(x)^2*exp(x^2*C(x)^4*exp(x^3*C(x)^6*exp(...)))) is the e.g.f. of A141357 = [1,1,5,55,945,21961,645013,22948815,...].
E.g.f.: A(x) = D(x*A(x)) where D(x) = exp(x*D(x)^3*exp(x^2*D(x)^6*exp(x^3*D(x)^9*exp(...)))) is the e.g.f. of A141358 = [1,1,7,106,2509,80956,3313579,164514904,...].
EXAMPLE
E.g.f.: A(x) = 1 + x + 9*x^2/2! + 175*x^3/3! + 5321*x^4/4! + 221001*x^5/5! +...
PROG
(PARI) {a(n)=local(A=1+x, F); for(i=0, n, for(j=0, n, F=exp((x*(A+x*O(x^n))^4)^(n-j+1)*F)); A=F); n!*polcoeff(A, n)}
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Jun 28 2008
STATUS
approved