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A093832
Values of r such that N(r)/r^2 > Pi, where N(r) is the number of integer lattice points (x,y) inside or on a circle of radius r.
4
1, 2, 3, 5, 10, 15, 20, 35, 51, 52, 85, 100, 230, 247, 370, 425, 489, 725, 730, 1073, 1310, 1865, 1997, 2480, 2831, 3072, 3424, 3750, 3861, 3921, 4025, 4339, 4771, 4885, 5559, 5949, 6203, 6411, 7045, 7084, 7410, 7605, 8931, 9308, 9435, 9646, 10829, 10930
OFFSET
1,2
LINKS
Eric Weisstein's World of Mathematics, Gauss's Circle Problem.
PROG
(PARI) A000328(n) = local(x, y, c, nn); c = 0; x = 0; nn = n*n; y = n; while (x < y, c += x; y--; x = sqrtint(nn - y*y)); 4*(n - y) + 8*c + (2*y + 1)^2; for (n = 1, 100000, if (A000328(n) > Pi*n*n, print(n))); \\ David Wasserman, Dec 05 2006
CROSSREFS
KEYWORD
nonn
AUTHOR
Eric W. Weisstein, Apr 17 2004
EXTENSIONS
Corrected and extended by David Wasserman, Dec 05 2006
Name corrected by Luis Mendo, Sep 24 2023
STATUS
approved