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 A129559 #9 Feb 18 2022 22:47:01 %S A129559 1,2,1,2,0,1,4,2,0,1,4,0,0,0,1,4,2,2,0,0,1,6,0,0,0,0,0,1,8,4,0,2,0,0, %T A129559 0,1,6,0,2,0,0,0,0,0,1,8,4,0,0,2,0,0,0,0,1,10,0,0,0,0,0,0,0,0,0,1,8,4, %U A129559 4,2,0,2,0,0,0,0,0,1,12,0,0,0,0,0,0,0,0,0,0,0,1 %N A129559 A054523 * A115361. %C A129559 row sums = A129527: (1, 3, 3, 7, 5, 9, 7, 15, ...). Left column = phi(2*n), A062570: (1, 2, 2, 4, 4, 4, 6, 8, ...). %H A129559 Andrew Howroyd, <a href="/A129559/b129559.txt">Table of n, a(n) for n = 1..1275</a> %F A129559 Equals A054523 * A115361 as infinite lower triangular matrices. %F A129559 T(n,k) = phi(2*n/k) for k | n, T(n,k) = 0 otherwise. - _Andrew Howroyd_, Aug 07 2018 %e A129559 First few rows of the triangle: %e A129559 1; %e A129559 2, 1; %e A129559 2, 0, 1; %e A129559 4, 2, 0, 1; %e A129559 4, 0, 0, 0, 1; %e A129559 4, 2, 2, 0, 0, 1; %e A129559 6, 0, 0, 0, 0, 0, 1; %e A129559 8, 4, 0, 2, 0, 0, 0, 1; %e A129559 ... %o A129559 (PARI) T(n, k)=if(n%k, 0, eulerphi(2*n/k)) \\ _Andrew Howroyd_, Aug 07 2018 %Y A129559 Column 1 is A062570. %Y A129559 Row sums are A129527 (inverse Moebius transform of A062570). %Y A129559 Cf. A054523, A115361. %K A129559 nonn,tabl %O A129559 1,2 %A A129559 _Gary W. Adamson_, Apr 20 2007 %E A129559 Terms a(56) and beyond from _Andrew Howroyd_, Aug 07 2018