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 A277644 #25 Feb 16 2025 08:33:37 %S A277644 1,2,3,4,6,7,8,9,11,12,13,14,15,17,18,19,20,22,23,24,25,26,28,29,30, %T A277644 31,33,34,35,36,37,39,40,41,42,44,45,46,47,48,50,51,52,53,55,56,57,58, %U A277644 60,61,62,63,64,66,67,68,69,71,72,73,74,75,77,78,79,80,82,83,84,85,86 %N A277644 Beatty sequence for sqrt(6)/2. %C A277644 Eggleton et al. show that k is in this sequence if and only if A277515(k)=3. %D A277644 R. B. Eggleton, J. S. Kimberley and J. A. MacDougall, Square-free rank of integers, submitted. %H A277644 Jason Kimberley, <a href="/A277644/b277644.txt">Table of n, a(n) for n = 1..10000</a> %H A277644 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/BeattySequence.html">Beatty Sequence</a>. %H A277644 <a href="/index/Be#Beatty">Index entries for sequences related to Beatty sequences</a>. %F A277644 a(n) = floor(n*sqrt(6)/2). %F A277644 a(n) = A000196(A032528(n)). %e A277644 a(5)=6 because the quotient of 3*5^2 by 2 is 37 which lies between 6^2 and 7^2. %t A277644 Floor[Range[100]*Sqrt[3/2]] (* _Paolo Xausa_, Jul 11 2024 *) %o A277644 (Magma) [Isqrt(3*n^2 div 2): n in [1..60]]; %o A277644 (PARI) a(n)=sqrtint(3*n^2\2) \\ _Charles R Greathouse IV_, Jul 11 2024 %Y A277644 Cf. A000196, A032528, A115754, A277515. Complement of A277645. %K A277644 nonn,easy %O A277644 1,2 %A A277644 _Jason Kimberley_, Oct 26 2016