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 A144735 #21 Oct 02 2024 07:40:54
%S A144735 1,-2,1,-2,-3,4,2,-6,0,4,-3,-2,-6,-6,16,5,0,-9,-5,6,4,-5,-2,-5,-6,-11,
%T A144735 -8,36,0,8,0,-24,0,0,0,16,0,6,-18,3,-3,-24,0,0,36,7,0,8,2,-34,-10,10,
%U A144735 -8,10,16
%N A144735 Square of triangle A054533 (matrix square), read by rows.
%C A144735 Row sums = A008683, mu(n).
%C A144735 Right border = squares of phi(n).
%F A144735 A054533^2, as an infinite lower triangular matrix.
%F A144735 T(n, k) = Sum_{s = k..n} R(n, s) * R(s, k) for n >= 1 and 1 <= k <= n, where R(n, s) = A054533(n, s) = Sum_{d | gcd(n,s)} d * mu(n/d). - _Petros Hadjicostas_, Jul 29 2019
%e A144735 First few rows of the triangle are as follows:
%e A144735 1;
%e A144735 -2, 1;
%e A144735 -2, -3, 4;
%e A144735 2, -6, 0, 4;
%e A144735 -3, -2, -6, -6, 16;
%e A144735 5, 0, -9, -5, 6, 4;
%e A144735 -5, -2, -5, -6, -11, -8, 36;
%e A144735 0, 8, 0, -24, 0, 0, 0, 16;
%e A144735 0, 6, -18, 3, -3, -24, 0, 0, 36;
%e A144735 7, 0, 8, 2, -34, -10, 10, -8, 10, 16;
%e A144735 ...
%Y A144735 Cf. A008683, A054533.
%K A144735 tabl,sign,more
%O A144735 1,2
%A A144735 _Gary W. Adamson_, Sep 20 2008