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 A382450 #28 Jun 10 2025 13:57:22 %S A382450 1,1,3,19,221,4597,174007,12328367,1674839513,443624694633, %T A382450 231531387336683,239620527240665643,493608618766634690997, %U A382450 2028225390820399637729437,16643586506902581140427736799,272938023130910288846692573380167,8947998686305041917555662919172783921 %N A382450 G.f. A(x) satisfies A(x) = 1/( 1 - x*A(2*x*A(x)) ). %F A382450 See A384777. %o A382450 (PARI) a(n, k=1) = if(k==0, 0^n, k*sum(j=0, n, 2^(n-j)*binomial(n+k, j)/(n+k)*a(n-j, j))); %Y A382450 Column k=1 of A384777. %K A382450 nonn %O A382450 0,3 %A A382450 _Seiichi Manyama_, Jun 10 2025