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.

A186511 Adjusted joint rank sequence of (f(i)) and (g(j)) with f(i) after g(j) when f(i)=g(j), where f(i)=i^2 and g(j)=-4+5j^2. Complement of A186512.

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%I A186511 #7 Mar 30 2012 18:57:19
%S A186511 2,3,4,6,7,8,10,11,13,14,16,17,18,20,21,23,24,26,27,28,30,31,33,34,36,
%T A186511 37,39,40,42,43,44,46,47,49,50,52,53,55,56,57,59,60,62,63,65,66,68,69,
%U A186511 70,72,73,75,76,78,79,81,82,83,85,86,88,89,91,92,94,95,96,98,99,101,102,104,105,107,108,110,111,112,114,115,117,118,120,121,123,124,125,127,128,130,131,133,134,136,137,138,140,141,143,144
%N A186511 Adjusted joint rank sequence of (f(i)) and (g(j)) with f(i) after g(j) when f(i)=g(j), where f(i)=i^2 and g(j)=-4+5j^2.  Complement of A186512.
%C A186511 See A186219 for a discussion of adjusted joint rank sequences.
%C A186511 The pairs (i,j) for which i^2=-4+5j^2 are (L(2h-1),F(2h-1)), where L=A000032 (Lucas numbers) and F=A000045 (Fibonacci numbers).
%F A186511 a(n)=n+floor(sqrt((n^2)/5+9/10))=A186511(n).
%F A186511 b(n)=n+floor(sqrt(5n^2-9/2))=A186512(n).
%e A186511 First, write
%e A186511 1..4..9..16..25..36..49..... (i^2)
%e A186511 1........16........41........(-4+5j^2)
%e A186511 Then replace each number by its rank, where ties are settled by ranking i^2 after -4+5j^2:
%e A186511 a=(2,3,4,6,7,8,10,11,13,14,16,...)=A186511
%e A186511 b=(1,5,9,12,15,19,22,25,29,32,...)=A186512.
%t A186511 (* adjusted joint rank sequences a and b, using general formula for ranking ui^2+vi+w and xj^2+yj+z *)
%t A186511 d = -1/2; u = 1; v = 0; w = 0; x = 5; y = 0; z =-4;
%t A186511 h[n_] := -y + (4 x (u*n^2 + v*n + w - z - d) + y^2)^(1/2);
%t A186511 a[n_] := n + Floor[h[n]/(2 x)];
%t A186511 k[n_] := -v + (4 u (x*n^2 + y*n + z - w + d) + v^2)^(1/2);
%t A186511 b[n_] := n + Floor[k[n]/(2 u)];
%t A186511 Table[a[n], {n, 1, 100}]  (* A186511 *)
%t A186511 Table[b[n], {n, 1, 100}]  (* A186512 *)
%Y A186511 Cf. A186219, A186499, A186500, A186512.
%K A186511 nonn
%O A186511 1,1
%A A186511 _Clark Kimberling_, Feb 22 2011