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 A380548 #10 Feb 07 2025 17:08:15 %S A380548 1,3,6,10,14,18,25,30,35,40,51,57,63,69,75,91,98,105,112,119,126,148, %T A380548 156,164,172,180,188,196,225,234,243,252,261,270,279,288,325,335,345, %U A380548 355,365,375,385,395,405,451,462,473,484,495,506,517,528,539,550,606 %N A380548 Main diagonal of A125585. %H A380548 Alois P. Heinz, <a href="/A380548/b380548.txt">Table of n, a(n) for n = 1..10000</a> %F A380548 a(n) = A125585(n,n). %p A380548 a:= n-> (m-> n+(m+1)*(n-1-m/2))(floor((sqrt(8*n-7)-1)/2)): %p A380548 seq(a(n), n=1..56); %Y A380548 Main diagonal of A125585. %K A380548 nonn,easy %O A380548 1,2 %A A380548 _Alois P. Heinz_, Jan 26 2025