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.

A186499 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 A186500.

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%I A186499 #10 Mar 30 2012 18:57:19
%S A186499 1,3,4,5,7,8,10,11,13,14,15,17,18,20,21,23,24,26,27,28,30,31,33,34,36,
%T A186499 37,39,40,41,43,44,46,47,49,50,52,53,55,56,57,59,60,62,63,65,66,68,69,
%U A186499 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 A186499 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 A186500.
%C A186499 See A186219 for a discussion of adjusted joint rank sequences.
%C A186499 The pairs (i,j) for which i^2=-4+5j^2 are (L(2h-2),F(2h-1)), where L=A000032 (Lucas numbers) and F=A000045 (Fibonacci numbers); compare this with the comment at A186511.
%F A186499 a(n)=n+floor((1/10)(sqrt(2n^2+7)))=A186499(n).
%F A186499 b(n)=n+floor(sqrt(5n^2-7/2))=A186500(n).
%e A186499 First, write
%e A186499 1..4..9..16..25..36..49..... (i^2)
%e A186499 1........16........41........(-4+5j^2)
%e A186499 Then replace each number by its rank, where ties are settled by ranking i^2 before -4+5j^2:
%e A186499 a=(1,3,4,5,7,8,10,11,13,14,15,17,18...)=A186499
%e A186499 b=(2,6,9,12,16,19,22,25,29,32,35,38,..)=A186500.
%t A186499 (* adjusted joint rank sequences a and b, using general formula for ranking ui^2+vi+w and xj^2+yj+z *)
%t A186499 d=1/2; u=1; v=0; w=0; x=5; y=0; z=4;
%t A186499 h[n_]:=-y+(4x(u*n^2+v*n+w-z-d)+y^2)^(1/2);
%t A186499 a[n_]:=n+Floor[h[n]/(2 x)];
%t A186499 k[n_]:=-v+(4u(x*n^2+y*n+z-w+d)+v^2)^(1/2);
%t A186499 b[n_]:=n + Floor[k[n]/(2 u)];
%t A186499 Table[a[n], {n, 1, 100}]  (* A186499 *)
%t A186499 Table[b[n], {n, 1, 100}]  (* A186500 *)
%Y A186499 Cf. A186219, A186500, A186511, A186512.
%K A186499 nonn
%O A186499 1,2
%A A186499 _Clark Kimberling_, Feb 22 2011