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 A385207 #13 Jun 21 2025 11:44:12 %S A385207 1,7,147,3430,79233,1714314,32471124,450360372,0,-313409171166, %T A385207 -15459345780879,-537166232508360,-15185812043764453, %U A385207 -348420909370148580,-5588125164812112720,0,4783756561471246040577,254794190560328322173970,9445124186699596552669050 %N A385207 G.f. A(x) satisfies A(x) = ( 1 + 49*x*A(x)^6 )^(1/7). %F A385207 a(n) = 49^n * binomial(6*n/7+1/7,n)/(6*n+1). %F A385207 G.f. A(x) satisfies A(x) = 1/A(-x*A(x)^5). %F A385207 G.f.: ( (1/x) * Series_Reversion(x/(1+49*x)^(6/7)) )^(1/6). %F A385207 a(7*n+1) = 0 for n > 0. %F A385207 G.f.: 1/B(-x), where B(x) is the g.f. of A385206. %o A385207 (PARI) a(n) = 49^n*binomial(6*n/7+1/7, n)/(6*n+1); %Y A385207 Cf. A385206, A385208. %Y A385207 Cf. A182122, A376636, A385205. %K A385207 sign %O A385207 0,2 %A A385207 _Seiichi Manyama_, Jun 21 2025