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 A187389 #8 Dec 05 2018 09:47:44
%S A187389 6,12,18,24,30,36,42,48,54,60,67,73,79,85,91,97,103,109,115,121,128,
%T A187389 134,140,146,152,158,164,170,176,182,188,195,201,207,213,219,225,231,
%U A187389 237,243,249,256,262,268,274,280,286,292,298,304,310,316,323,329,335,341,347,353,359,365,371,377,384,390,396,402,408,414,420,426
%N A187389 a(n) = floor(r*n), where r = 1 + sqrt(7) + sqrt(6); complement of A187390.
%C A187389 A187389 and A187390 are the Beatty sequences based on r=1+sqrt(7)+sqrt(6) and s=1+sqrt(7)-sqrt(6); 1/r+1/s=1.
%F A187389 a(n)=floor(r*n), where r=1+sqrt(7)+sqrt(6).
%t A187389 k=7; r=1+k^(1/2)+(k-1)^(1/2); s=1+k^(1/2)-(k-1)^(1/2);
%t A187389 Table[Floor[r*n],{n,1,80}] (* A187389 *)
%t A187389 Table[Floor[s*n],{n,1,80}] (* A187390 *)
%Y A187389 Cf. A187390.
%K A187389 nonn
%O A187389 1,1
%A A187389 _Clark Kimberling_, Mar 09 2011