A184403 - OEIS

A184403

"Types" (parities of i and j) when all the numbers i+j*r are ranked, where r=sqrt(2), i>=0, j>=0.

4, 2, 3, 4, 1, 4, 2, 3, 2, 4, 3, 1, 4, 2, 1, 3, 4, 2, 4, 3, 1, 2, 4, 2, 3, 1, 3, 4, 2, 4, 1, 3, 1, 4, 2, 4, 2, 3, 1, 3, 2, 4, 2, 3, 4, 1, 3, 1, 4, 2, 4, 1, 2, 3, 1, 4, 3, 2, 4, 2, 3, 4, 1, 3, 2, 1, 4, 2, 3, 4, 1, 2, 3, 1, 4, 3, 2, 4, 1, 2, 3, 4, 1, 4, 3, 2, 1, 4, 2, 3, 4, 1, 2, 3, 2, 1

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

LINKS

Table of n, a(n) for n=1..96.

FORMULA

Let s(n)=i(n)+r*j(n) be the sequence obtained by arranging in increasing order all the numbers i+j*r, where

r=2^(1/2) and i>=0, j>=0. Then

a(n)=1 if i(n) is odd and j(n) is odd (n in A184399);

a(n)=2 if i(n) is odd and j(n) is even (n in A184400);

a(n)=3 if i(n) is even and j(n) is odd (n in A184401);

a(n)=4 if i(n) is even and j(n) is even (n in A184402).