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 A354266 #7 May 22 2022 05:33:46 %S A354266 2,4,2,6,3,6,2,8,4,6,2,10,3,9,4,8,2,12,4,10,6,8,3,12,5,10,6,9,2,14,4, %T A354266 12,6,10,2,16,3,15,4,14,6,12,8,10,2,18,4,16,5,15,6,14,8,12,3,18,6,15, %U A354266 7,14,9,12,2,20,4,18,6,16,8,14,10,12,2,22,3,21 %N A354266 Pairs of integers (s, t) such that 0 < s < t and gcd(s, t) > 1, where the pairs are generated by the boustrophedonic Cantor enumeration A319571. %e A354266 The sequence of pairs starts: %e A354266 (2, 4), (2, 6), (3, 6), (2, 8), (4, 6), (2, 10), (3, 9), (4, 8), (2, 12), (4, 10),(6, 8), (3, 12), (5, 10), (6, 9), (2, 14), (4, 12), (6, 10), (2, 16), (3, 15),(4, 14), (6, 12), (8, 10), ... %o A354266 (Julia) %o A354266 function A354266List(upto) %o A354266 L = Int[] %o A354266 for n in 1:upto %o A354266 d = div(isqrt(8n + 1) - 1, 2) %o A354266 s = n - div(d*(d + 1), 2) %o A354266 t = d - s %o A354266 if s > 0 && s < t && gcd(s, t) > 1 %o A354266 push!(L, s) %o A354266 push!(L, t) %o A354266 end %o A354266 end %o A354266 L end %o A354266 println(A354266List(303)) %Y A354266 Cf. A319571. %K A354266 nonn %O A354266 1,1 %A A354266 _Peter Luschny_, May 21 2022