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 A100154 #19 Aug 06 2025 08:40:43
%S A100154 1,60,282,772,1635,2976,4900,7512,10917,15220,20526,26940,34567,43512,
%T A100154 53880,65776,79305,94572,111682,130740,151851,175120,200652,228552,
%U A100154 258925,291876,327510,365932,407247,451560,498976,549600,603537,660892,721770,786276,854515
%N A100154 Structured truncated icosahedral numbers.
%H A100154 Vincenzo Librandi, <a href="/A100154/b100154.txt">Table of n, a(n) for n = 1..5000</a>
%H A100154 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (4,-6,4,-1).
%F A100154 a(n) = (1/2)*n*(35*n^2 - 47*n + 14).
%F A100154 G.f.: x*(1 + 56*x + 48*x^2)/(1-x)^4. - _Colin Barker_, Feb 12 2012
%F A100154 From _Elmo R. Oliveira_, Aug 05 2025: (Start)
%F A100154 E.g.f.: exp(x)*x*(35*x^2 + 58*x + 2)/2.
%F A100154 a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4) for n > 4. (End)
%t A100154 LinearRecurrence[{4, -6, 4, -1},{1, 60, 282, 772}, 50] (* _Paolo Xausa_, Aug 06 2025 *)
%o A100154 (Magma) [(1/6)*(105*n^3-141*n^2+42*n): n in [1..40]]; // _Vincenzo Librandi_, Jul 19 2011
%Y A100154 Cf. A100153, A100155 for adjacent structured Archimedean solids; A100145 for more on structured polyhedral numbers.
%K A100154 easy,nonn
%O A100154 1,2
%A A100154 James A. Record (james.record(AT)gmail.com), Nov 07 2004