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A183993
"Types" (parities of i and j) when all the numbers i+j*r are ranked, where r=golden ratio, i>=0, j>=0.
9
4, 2, 3, 4, 1, 2, 4, 3, 4, 2, 1, 3, 2, 4, 3, 1, 4, 2, 4, 1, 3, 2, 4, 2, 3, 1, 4, 3, 2, 4, 1, 3, 2, 1, 4, 2, 3, 4, 1, 4, 3, 2, 4, 1, 2, 3, 2, 1, 4, 3, 2, 3, 4, 1, 4, 3, 2, 1, 4, 1, 2, 3, 4, 2, 1, 4, 3, 2, 3, 4, 1, 2, 4, 3, 2, 1, 4, 3, 1, 2
OFFSET
1,1
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 is the golden mean ((1+sqrt(5))/2), and i>=0, j>=0. Then
a(n)=1 if i(n) is odd and j(n) is odd (n in A183989);
a(n)=2 if i(n) is odd and j(n) is even (n in A183990);
a(n)=3 if i(n) is even and j(n) is odd (n in A183991);
a(n)=4 if i(n) is even and j(n) is even (n in A183992).
EXAMPLE
(See the examples at A183989-A183992.)
KEYWORD
nonn
AUTHOR
Clark Kimberling, Jan 08 2011
EXTENSIONS
I edited the definition slightly. - N. J. A. Sloane, Jan 11 2011
STATUS
approved