cp's OEIS Frontend

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.

A186513 Adjusted joint rank sequence of (f(i)) and (g(j)) with f(i) before g(j) when f(i)=g(j), where f(i)=i^2 and g(j)=4+5j^2. Complement of A186514.

This page as a plain text file.
%I A186513 #6 Mar 30 2012 18:57:19
%S A186513 1,2,3,5,7,8,9,11,12,14,15,17,18,20,21,23,24,25,27,28,30,31,33,34,36,
%T A186513 37,39,40,41,43,44,46,47,49,50,52,53,54,56,57,59,60,62,63,65,66,67,69,
%U A186513 70,72,73,75,76,78,79,81,82,83,85,86,88,89,91,92,94,95,96,98,99,101,102,104,105,107,108,109,111,112,114,115,117,118,120,121,123,124,125,127,128,130,131,133,134,136,137,138,140,141,143,144
%N A186513 Adjusted joint rank sequence of (f(i)) and (g(j)) with f(i) before g(j) when f(i)=g(j), where f(i)=i^2 and g(j)=4+5j^2.  Complement of A186514.
%C A186513 See A186219 for a discussion of adjusted joint rank sequences.
%C A186513 The pairs (i,j) for which i^2=4+5j^2 are (L(2h),F(2h)), where L=A000032 (Lucas numbers) and F=A000045 (Fibonacci numbers).
%F A186513 a(n)=n+floor(sqrt((n^2)/5-9/10))=A186513(n).
%F A186513 b(n)=n+floor(sqrt(5n^2+9/2))=A186514(n).
%e A186513 First, write
%e A186513 1..4..9..16..25..36..49..... (i^2)
%e A186513 ......9.....24.......49.. (4+5j^2)
%e A186513 Then replace each number by its rank, where ties are settled by ranking i^2 before 4+5j^2:
%e A186513 a=(1,2,3,5,7,8,9,11,12,14,15,17,..)=A186513
%e A186513 b=(4,6,10,13,16,19,22,26,29,32,...)=A186514.
%t A186513 (* adjusted joint rank sequences a and b, using general formula for ranking ui^2+vi+w and xj^2+yj+z *)
%t A186513 d = 1/2; u = 1; v = 0; w = 0; x = 5; y = 0; z = 4;
%t A186513 h[n_] := -y + (4 x (u*n^2 + v*n + w - z - d) + y^2)^(1/2);
%t A186513 a[n_] := n + Floor[h[n]/(2 x)];
%t A186513 k[n_] := -v + (4 u (x*n^2 + y*n + z - w + d) + v^2)^(1/2);
%t A186513 b[n_] := n + Floor[k[n]/(2 u)];
%t A186513 Table[a[n], {n, 1, 100}]  (* A186513 *)
%t A186513 Table[b[n], {n, 1, 100}]  (* A186514 *)
%Y A186513 Cf. A186219, A186514, A186515, A186516.
%K A186513 nonn
%O A186513 1,2
%A A186513 _Clark Kimberling_, Feb 22 2011