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 A104764 #10 Aug 08 2015 21:33:21 %S A104764 1,3,1,4,3,1,7,4,3,1,11,7,4,3,1,18,11,7,4,3,1,29,18,11,7,4,3,1,47,29, %T A104764 18,11,7,4,3,1,76,47,29,18,11,7,4,3,1,123,76,47,29,18,11,7,4,3,1,199, %U A104764 123,76,47,29,18,11,7,4,3,1,322,199,123 %N A104764 Triangle T(n,k) = Lucas(n-k+1) read by rows, 1<=k<=n. %F A104764 T(n,k) = A000204(n-k+1). %e A104764 First few rows of the triangle are: %e A104764 1; %e A104764 3, 1; %e A104764 4, 3, 1; %e A104764 7, 4, 3, 1; %e A104764 11, 7, 4, 3, 1; %e A104764 18, 11, 7, 4, 3, 1; %e A104764 ... %p A104764 A104764 := proc(n,k) %p A104764 A000204(n-k+1) ; %p A104764 end proc: %p A104764 seq(seq(A104764(n,k),k=1..n),n=1..13) ; # _R. J. Mathar_, Oct 30 2011 %Y A104764 Cf. A104765, A000204. %K A104764 nonn,tabl,easy %O A104764 1,2 %A A104764 _Gary W. Adamson_, Mar 24 2005