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 A133463 #8 Jul 21 2021 13:42:12
%S A133463 2,3,4,5,6,9,12,15,18,27,36,45,54,81,108,135,162,243,324,405,486,729,
%T A133463 972,1215,1458,2187,2916,3645,4374,6561,8748,10935,13122,19683,26244,
%U A133463 32805,39366,59049,78732,98415,118098,177147,236196,295245,354294
%N A133463 Partial sums of the sequence that starts with 2 and is followed by A111575.
%F A133463 a(4n) = 2*A111575(4n). a(4n+1)= 3*A111575(4n+1). a(4n+2)= 4*A111575(4n+2). a(4n+3)= 5*A111575(4n+3). - _R. J. Mathar_, Jan 12 2008
%p A133463 A111575 := proc(n) 3^(floor(n/4)) ; end: A133463 := proc(n) 2+add( A111575(i),i=0..n-1) ; end: seq(A133463(n),n=0..80) ; # _R. J. Mathar_, Jan 12 2008
%t A133463 Accumulate[Join[{2},With[{pt=3^Range[0,15]},Sort[Join[pt,pt,pt,pt]]]]] (* _Harvey P. Dale_, Jul 21 2021 *)
%K A133463 nonn
%O A133463 0,1
%A A133463 _Paul Curtz_, Nov 28 2007
%E A133463 Edited and extended by _R. J. Mathar_, Jan 12 2008