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 A198585 #15 Feb 05 2025 14:47:13 %S A198585 5,5,5,85,5,341,85,5,341,85,5,341,85,5461,5,341,21845,85,5461,5,341, %T A198585 21845,85,5461,5,341,21845,85,5461,349525,5,341,21845,1398101,85,5461, %U A198585 349525,5,341,21845,1398101,85,5461,349525,5,341,21845,1398101,85,5461 %N A198585 The second odd number appearing in the Collatz sequence starting with A198584(n). %C A198585 A198586 has the unique numbers appearing in this sequence. %H A198585 T. D. Noe, <a href="/A198585/b198585.txt">Table of n, a(n) for n = 1..1009</a> %F A198585 a(n) = A079813(1 + (-1 + b(n))^2 + c(n))*(A198586(2*(1 + c(n))) - A198586(3 - 2*(b(n) - c(n)))) + A198586(3 - 2*(b(n) - c(n))) where b(n) = ceiling(sqrt(n)/sqrt(3)) and c(n) = (-1+n-3*(b(n)-1)^2) mod (2*b(n)-1). - _Alan Michael Gómez Calderón_, Jan 22 2025 %Y A198585 Cf. A079813, A198584, A198586. %K A198585 nonn %O A198585 1,1 %A A198585 _T. D. Noe_, Oct 28 2011