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A319289
The x coordinates of the shell enumeration of N X N where N = {0, 1, 2, ...} (A319514).
5
0, 0, 1, 1, 2, 2, 2, 1, 0, 0, 1, 2, 3, 3, 3, 3, 4, 4, 4, 4, 4, 3, 2, 1, 0, 0, 1, 2, 3, 4, 5, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 6, 6, 5, 4, 3, 2, 1, 0, 0, 1, 2, 3, 4, 5, 6, 7, 7, 7, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 7, 6, 5, 4, 3, 2, 1, 0, 0, 1, 2, 3, 4, 5
OFFSET
0,5
COMMENTS
See A319514 for comments and references.
LINKS
PROG
(Julia)
function A319289(n)
m = x = isqrt(n)
y = n - x^2
x <= y && ((x, y) = (2x - y, x))
isodd(m) ? y : x
end
CROSSREFS
Cf. A319514.
Sequence in context: A334889 A078336 A076441 * A124747 A334888 A039981
KEYWORD
nonn
AUTHOR
Peter Luschny, Sep 23 2018
STATUS
approved