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A319290
The y coordinates of the shell enumeration of N X N where N = {0, 1, 2, ...}(A319514).
5
0, 1, 1, 0, 0, 1, 2, 2, 2, 3, 3, 3, 3, 2, 1, 0, 0, 1, 2, 3, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 4, 3, 2, 1, 0, 0, 1, 2, 3, 4, 5, 6, 6, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 7, 6, 5, 4, 3, 2, 1, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 9, 9, 9, 9, 9, 9
OFFSET
0,7
COMMENTS
See A319514 for comments and references.
LINKS
PROG
(Julia)
function A319290(n)
m = x = isqrt(n)
y = n - x^2
x <= y && ((x, y) = (2x - y, x))
isodd(m) ? x : y
end
CROSSREFS
Cf. A319514.
Sequence in context: A292995 A037179 A127971 * A230516 A192688 A156752
KEYWORD
nonn
AUTHOR
Peter Luschny, Sep 23 2018
STATUS
approved