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A326421 Least numbers k such that A088534(k) is nondecreasing. 2
0, 1, 3, 4, 7, 9, 12, 13, 16, 19, 21, 25, 27, 28, 31, 36, 37, 39, 43, 48, 49, 91, 133, 147, 169, 196, 217, 247, 259, 273, 301, 343, 361, 364, 399, 403, 427, 441, 469, 481, 507, 511, 532, 553, 559, 588, 589, 637, 931, 1183, 1519, 1729, 2821, 3367 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,3
COMMENTS
Least squared radius of a circle around a grid point of the hexagonal lattice such that the number of grid points on this circle is not smaller than the number of grid points on any circle around a grid point of the hexagonal lattice with smaller radius. a(1) = 0 by convention.
LINKS
PROG
(PARI) \\ after M. F. Hasler's A088534(n, d)
r2=0; for(k=0, 3500, my(a088534=sum(x=0, sqrt(k\3), sum(y=max(x, sqrtint(k-x^2)\2), sqrtint(k-2*x^2), x^2+x*y+y^2==k))); if(a088534>=r2, r2=a088534; print1(k, ", ")))
CROSSREFS
Sequence in context: A352274 A035238 A003136 * A329963 A034022 A198772
KEYWORD
nonn
AUTHOR
Hugo Pfoertner, Sep 12 2019
STATUS
approved

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Last modified March 28 05:39 EDT 2024. Contains 371235 sequences. (Running on oeis4.)