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A186541 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)=-2+3j^2.  Complement of A186542. 4
2, 3, 4, 6, 8, 9, 11, 12, 14, 15, 17, 18, 20, 22, 23, 25, 26, 28, 30, 31, 33, 34, 36, 37, 39, 41, 42, 44, 45, 47, 48, 50, 52, 53, 55, 56, 58, 59, 61, 63, 64, 66, 67, 69, 70, 72, 74, 75, 77, 78, 80, 82, 83, 85, 86, 88, 89, 91, 93, 94, 96, 97, 99, 100, 102, 104, 105, 107, 108, 110, 112, 113, 115, 116, 118, 119, 121, 123, 124, 126, 127, 129, 130, 132, 134, 135, 137, 138, 140, 141, 143, 145, 146, 148, 149, 151, 153, 154, 156, 157 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

See A186219 for a discussion of adjusted joint rank sequences.

LINKS

Table of n, a(n) for n=1..100.

FORMULA

a(n)=n+floor(sqrt((1/3)n^2+5/6))=A186541(n).

b(n)=n+floor(sqrt(3n^2-5/2))=A186542(n).

EXAMPLE

First, write

1..4..9..16..25..36..49..... (i^2)

.........10.....25.....46.. (-2+3j^2)

Then replace each number by its rank, where ties are settled by ranking i^2 after -2+3j^2:

a=(2,3,4,6,8,9,11,12,14,15,17,18,..)=A186541

b=(1,5,7,10,13,16,19,21,24,27,29...)=A186542.

MATHEMATICA

(* adjusted joint rank sequences a and b, using general formula for ranking ui^2+vi+w and xj^2+yj+z *)

d = -1/2; u = 1; v = 0; w = 0; x = 3; y = 0; z = -2;

h[n_] := -y + (4 x (u*n^2 + v*n + w - z - d) + y^2)^(1/2);

a[n_] := n + Floor[h[n]/(2 x)];

k[n_] := -v + (4 u (x*n^2 + y*n + z - w + d) + v^2)^(1/2);

b[n_] := n + Floor[k[n]/(2 u)];

Table[a[n], {n, 1, 100}]  (* A186539 *)

Table[b[n], {n, 1, 100}]  (* A186540 *)

CROSSREFS

Cf. A186219, A186539, A186540, A186542.

Sequence in context: A235933 A335878 A233133 * A207432 A020900 A333309

Adjacent sequences:  A186538 A186539 A186540 * A186542 A186543 A186544

KEYWORD

nonn

AUTHOR

Clark Kimberling, Feb 23 2011

STATUS

approved

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Last modified May 16 08:07 EDT 2021. Contains 343940 sequences. (Running on oeis4.)