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 A115240 #9 Feb 07 2016 21:33:44 %S A115240 0,0,3,10,33,104,328,1031,3241,10183,31991,100503,315740,991928, %T A115240 3116234,9789941,30756009,96622854,303549648,953629346,2995914948, %U A115240 9411944394,29568495367,92892167824,291829352014,916808948392,2880240257014 %N A115240 a(n) = A001672(n) - A115239(n). %H A115240 G. C. Greubel, <a href="/A115240/b115240.txt">Table of n, a(n) for n = 1..1000</a> %e A115240 a(5) = A001672(5) - A115239(5) = 306 - 273 = 33. %t A115240 a[1] = Floor[Pi]; a[n_] := a[n] = Floor[a[n - 1]*Pi]; Array[ Floor[Pi^# ] - a[ # ] &, 27] (* _Robert G. Wilson v_ *) %Y A115240 Cf. A001672, A115239. %K A115240 nonn %O A115240 1,3 %A A115240 _Hieronymus Fischer_, Jan 17 2006 %E A115240 More terms from _Robert G. Wilson v_, Jan 18 2006