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 A129234 #11 Jan 17 2025 09:09:35 %S A129234 1,2,2,3,0,3,4,3,0,4,5,0,0,0,5,6,4,4,0,0,6,7,0,0,0,0,0,7,8,5,0,5,0,0, %T A129234 0,8,9,0,5,0,0,0,0,0,9,10,6,0,0,6,0,0,0,0,10,11,0,0,0,0,0,0,0,0,0,11, %U A129234 12,7,6,6,0,7,0,0,0,0,0,12,13,0,0,0,0,0,0,0,0,0,0,0,13,14,8,0,0,0,0,8,0,0,0,0,0,0,14 %N A129234 Triangle read by rows: T(n,k) = n/k + k - 1 if n mod k = 0; otherwise T(n,k)=0 (1 <= k <= n). %C A129234 Row sums = A129235: (1, 4, 6, 11, 10, 20, 14, ...). Moebius transform of A129234 = A129236. Inverse Moebius transform of A129234 = A129237. %F A129234 G.f. = G(t,z) = Sum_{k>=1} t^k*z^k*(k-(k-1)*z^k)/(1-z^k)^2. - _Emeric Deutsch_, Apr 17 2007 %e A129234 First few rows of the triangle: %e A129234 1; %e A129234 2, 2; %e A129234 3, 0, 3; %e A129234 4, 3, 0, 4; %e A129234 5, 0, 0, 0, 5; %e A129234 6, 4, 4, 0, 0, 6; %e A129234 7, 0, 0, 0, 0, 0, 7; %e A129234 ... %p A129234 T:=proc(n,k) if n mod k = 0 then n/k+k-1 else 0 fi end: for n from 1 to 16 do seq(T(n,k),k=1..n) od; # yields sequence in triangular form - _Emeric Deutsch_, Apr 17 2007 %t A129234 T[n_,k_]:=If[Mod[n,k]==0,n/k+k-1,0];Table[T[n,k],{n,14},{k,n}]//Flatten (* _James C. McMahon_, Jan 17 2025 *) %o A129234 (PARI) row(n) = vector(n, k, if (!(n%k), n/k + k - 1, 0)); \\ _Michel Marcus_, Jan 17 2025 %Y A129234 Cf. A129235, A129236, A129237. %K A129234 nonn,tabl %O A129234 1,2 %A A129234 _Gary W. Adamson_, Apr 05 2007 %E A129234 Edited by _Emeric Deutsch_, Apr 17 2007