cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A144005 E.g.f. A(x) satisfies: A(x) = 1 + Series_Reversion( Integral A(-x) dx ).

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%I A144005 #6 Jul 24 2022 22:07:49
%S A144005 1,1,1,2,7,33,201,1479,12842,127952,1440989,18070767,249766088,
%T A144005 3769280801,61654447712,1085974748430,20485430748783,411839042136379,
%U A144005 8786499316562396,198174104269740313,4708919322491690592
%N A144005 E.g.f. A(x) satisfies: A(x) = 1 + Series_Reversion( Integral A(-x) dx ).
%C A144005 This is essentially the same sequence as A014623. - _N. J. A. Sloane_, Jul 24 2022
%C A144005 Compare the definition of e.g.f. A(x) to the trivial statement:
%C A144005 if F(x) = 1 + Series_Reversion( Integral F(-x)^2 dx ) then F(x) = 1/(1-x).
%F A144005 E.g.f. satisfies: A(x) = 1 + Integral 1/A(1 - A(x)) dx. - _Paul D. Hanna_, Jul 10 2015
%e A144005 E.g.f: A(x) = 1 + x + x^2/2! + 2*x^3/3! + 7*x^4/4! + 33*x^5/5! +...
%e A144005 Let I(x) = Series_Reversion(A(x) - 1) = Integral A(-x) dx then
%e A144005 I(x) = x - x^2/2! + x^3/3! - 2*x^4/4! + 7*x^5/5! - 33*x^6/6! +...
%o A144005 (PARI) {a(n)=local(A=1+x+x*O(x^n)); for(i=0,n,A=1+serreverse(intformal(subst(A,x,-x)^1)));n!*polcoeff(A,n)}
%Y A144005 Cf. A014623; A144002.
%K A144005 nonn
%O A144005 0,4
%A A144005 _Paul D. Hanna_, Sep 07 2008