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 A367245 #5 Nov 12 2023 13:31:04
%S A367245 0,11,135,1103,7551,46871,273735,1534943,8366031,44674151,234982935,
%T A367245 1222071983,6301114911,32274971831,164471580135,834802180223,
%U A367245 4223960206191,21320114811911,107403378865335,540232762595663,2714041233191871,13621757688226391,68315120054438535
%N A367245 a(n) is the number of n-digit numbers whose difference between the largest and smallest digits is equal to 4.
%C A367245 a(n) is the number of n-digit numbers in A366961.
%H A367245 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (12,-47,60).
%F A367245 a(n) = 29*5^(n-1) - 47*4^(n-1) + 2*3^(n+1).
%F A367245 a(n) = 12*a(n-1) - 47*a(n-2) + 60*a(n-3) for n > 3.
%F A367245 O.g.f.: x^2*(11 + 3*x)/((1 - 3*x)*(1 - 4*x)*(1 - 5*x)).
%F A367245 E.g.f.: (116*exp(5*x) - 235*exp(4*x) + 120*exp(3*x) - 1)/20.
%t A367245 LinearRecurrence[{12,-47,60},{0,11,135},23]
%Y A367245 Cf. A366961.
%Y A367245 Cf. A000244, A000302, A000351.
%Y A367245 Cf. A367243, A367244, A367246, A367247, A367248, A367249, A367250.
%K A367245 nonn,base,easy
%O A367245 1,2
%A A367245 _Stefano Spezia_, Nov 11 2023