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A096891
Least hypotenuse of primitive Pythagorean triangles with odd leg 2n+1.
15
5, 13, 25, 41, 61, 85, 17, 145, 181, 29, 265, 313, 365, 421, 481, 65, 37, 685, 89, 841, 925, 53, 1105, 1201, 149, 1405, 73, 185, 1741, 1861, 65, 97, 2245, 269, 2521, 2665, 317, 85, 3121, 3281, 3445, 157, 425, 3961, 109, 485, 193, 4705, 101, 5101, 5305, 137
OFFSET
1,1
COMMENTS
Ordered terms are A020882. - Paul Curtz, Sep 08 2008
Least value of x^2 + y^2 with gcd(x,y) = 1 such that y^2 - x^2 = 2n+1. - Thomas Ordowski, Apr 02 2017
MATHEMATICA
f[n_] := Block[{k = 2}, While[c = Sqrt[(2n + 1)^2 + k^2]; ! IntegerQ@ c || GCD[2n + 1, c, k] > 1, k += 2]; c]; Array[f, 52] (* Robert G. Wilson v, Mar 18 2014 *)
KEYWORD
nonn
AUTHOR
Ray Chandler, Jul 14 2004
STATUS
approved