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.
%I A268170 #6 Jan 28 2016 11:57:55 %S A268170 1,1,2,5,16,65,326,1947,13410,104181,900214,8566655,89055224, %T A268170 1004141647,12204369138,159036267519,2211764983734,32696763676521, %U A268170 511987792322430,8465194670035767,147370831072230860,2694506417687396995,51622643862824956898,1034153511794063402519,21621325640846679627146 %N A268170 E.g.f. A(x) satisfies: A(x) = exp( Integral B(x) dx ) such that B(x) = exp(1+x - exp(x)) * exp( Integral A(x) dx ), where the constant of integration is zero. %C A268170 Compare to: F(x) = exp( Integral G(x) dx ) such that G(x) = exp(1-exp(x)) * exp( Integral F(x) dx ) holds when F(x) = exp(x). %e A268170 E.g.f.: A(x) = 1 + x + 2*x^2/2! + 5*x^3/3! + 16*x^4/4! + 65*x^5/5! + 326*x^6/6! + 1947*x^7/7! + 13410*x^8/8! + 104181*x^9/9! + 900214*x^10/10! + 8566655*x^11/11! +... %e A268170 such that log(A(x)) = Integral B(x) dx %e A268170 where %e A268170 B(x) = 1 + x + x^2/2! + 2*x^3/3! + 9*x^4/4! + 46*x^5/5! + 245*x^6/6! + 1474*x^7/7! + 10315*x^8/8! + 82174*x^9/9! + 726591*x^10/10! + 7038632*x^11/11! + 74216949*x^12/12! +...+ A268171(n)*x^n/n! +... %e A268170 and A(x) and B(x) satisfy: %e A268170 (1) A(x) = B'(x)/B(x) + exp(x) - 1, %e A268170 (2) B(x) = A'(x)/A(x), %e A268170 (3) log(A(x)) = Integral B(x) dx, %e A268170 (4) log(B(x)) = Integral A(x) dx + 1+x - exp(x). %e A268170 RELATED SERIES. %e A268170 log(A(x)) = x + x^2/2! + x^3/3! + 2*x^4/4! + 9*x^5/5! + 46*x^6/6! + 245*x^7/7! + 1474*x^8/8! + 10315*x^9/9! + 82174*x^10/10! + 726591*x^11/11! + 7038632*x^12/12! +... %e A268170 Let J(x) equal the series reversion of log(A(x)); then %e A268170 J(x) = x - x^2/2! + 2*x^3/3! - 7*x^4/4! + 31*x^5/5! - 172*x^6/6! + 1155*x^7/7! - 9027*x^8/8! + 80676*x^9/9! - 811727*x^10/10! + 9075333*x^11/11! - 111633356*x^12/12! +... %e A268170 where A(J(x)) = exp(x). %o A268170 (PARI) {a(n) = my(A=1+x, B=1+x); for(i=0, n, A = exp( intformal( B + x*O(x^n) ) ); B = exp(1+x - exp(x +x*O(x^n)) + intformal( A ) ) ); n!*polcoeff(A, n)} %o A268170 for(n=0, 30, print1(a(n), ", ")) %Y A268170 Cf. A266328, A266329, A266490, A268171. %K A268170 nonn %O A268170 0,3 %A A268170 _Paul D. Hanna_, Jan 27 2016