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 A323120 #6 Jan 07 2019 13:38:35 %S A323120 0,0,2,3,12,23,58,123,266,557,1168,2400,4911,9982,20196,40643,81499, %T A323120 162899,324678,645404,1280042,2533565,5005449,9872464,19442206, %U A323120 38234945,75096856,147324049,288705896,565201569,1105475313,2160338661,4218403428,8230986025 %N A323120 Number of compositions of n where the difference between largest and smallest parts equals three. %H A323120 Alois P. Heinz, <a href="/A323120/b323120.txt">Table of n, a(n) for n = 3..3509</a> %F A323120 a(n) ~ c * d^n, where d = A086088 = 1.92756197548292530426190586173662216869855... is the real root of the equation d^4 - d^3 - d^2 - d - 1 = 0 and c = 0.566342887702651534849280952809003081138499070062015666102331676335... is the real root of the equation 563*c^4 - 563*c^3 + 174*c^2 - 22*c + 1 = 0. - _Vaclav Kotesovec_, Jan 07 2019 %Y A323120 Column k=3 of A214258. %K A323120 nonn %O A323120 3,3 %A A323120 _Alois P. Heinz_, Jan 05 2019