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 A307729 #51 Jun 16 2020 14:21:14 %S A307729 0,0,1,0,1,2,1,2,4,5,4,6,8,6,13,11,18,17,19,23,22,30,29,32,37,40,54, %T A307729 49,63,63,65,73,79,94,90,98,113,110,138,127,151,154,161,181,180,210, %U A307729 209,216,240,247,279,269,297,320,318,348,359,402,396,401,441,440 %N A307729 Sum of the smallest sides of all acute integer triangles with perimeter n. %H A307729 Wikipedia, <a href="https://en.wikipedia.org/wiki/Integer_triangle">Integer Triangle</a> %F A307729 a(n) = Sum_{k=1..floor(n/3)} Sum_{i=k..floor((n-k)/2)} (1-sign(floor((n-i-k)^2/(i^2+k^2)))) * sign(floor((i+k)/(n-i-k+1))) k. %t A307729 Table[Sum[Sum[k*(1 - Sign[Floor[(n - i - k)^2/(i^2 + k^2)]]) Sign[Floor[(i + k)/(n - i - k + 1)]], {i, k, Floor[(n - k)/2]}], {k, Floor[n/3]}], {n, 100}] %Y A307729 Cf. A070093. %K A307729 nonn %O A307729 1,6 %A A307729 _Wesley Ivan Hurt_, May 15 2019