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 A171245 #14 Aug 23 2021 06:10:24 %S A171245 7,-790,12016,-3748629,1730431227,-3015428685,8172837003,-34313104062, %T A171245 114738541304,-620832653094,2474837590227,-45157370341559, %U A171245 1726856191927439,-6094457427533473,12791098836150787,-51642743340781227,325724575136738920,-1813676066719263909 %N A171245 Reciprocals of the deviation of continued fraction convergents from Pi. %C A171245 Clearly the terms alternate in sign, but the initial choice of sign was arbitrary. %e A171245 The first convergent to Pi, 3, is just over 1/7 too low, so 7 is the first term. %e A171245 The second convergent, 22/7, is 0.001264+ too high, which is just over 1/790, so -790 is the second term. %o A171245 (PARI) for(x=1,10,t=contfracpnqn(contfrac(Pi,x));print(truncate(1/(Pi-t[1,1]/t[2,1])))) %Y A171245 Cf. A001203. %K A171245 sign %O A171245 1,1 %A A171245 _Phil Carmody_, Dec 06 2009 %E A171245 More terms from _Jinyuan Wang_, Aug 23 2021