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A055526
Shortest hypotenuse of a Pythagorean triangle with n as length of a leg.
8
5, 5, 13, 10, 25, 10, 15, 26, 61, 13, 85, 50, 17, 20, 145, 30, 181, 25, 29, 122, 265, 25, 65, 170, 45, 35, 421, 34, 481, 40, 55, 290, 37, 39, 685, 362, 65, 41, 841, 58, 925, 55, 51, 530, 1105, 50, 175, 130, 85, 65, 1405, 90, 73, 65, 95, 842, 1741, 61, 1861, 962, 65
OFFSET
3,1
COMMENTS
Smallest k>n such that the squarefree part of k+n equals the squarefree part of k-n - Benoit Cloitre, May 26 2002
FORMULA
a(n) = sqrt(n^2+A055527(n)^2).
MATHEMATICA
core[n_] := core[n] = Times @@ Map[#[[1]]^Mod[#[[2]], 2] &, FactorInteger[n]];
A055526[n_] := Block[{k = n}, While[core[++k+n] != core[k-n]]; k];
Array[A055526, 100, 3] (* Paolo Xausa, Feb 29 2024 *)
PROG
(PARI) for(n=3, 105, s=n+1; while(abs(core(s+n)-core(s-n))>0, s++); print1(s, ", "))
KEYWORD
nonn
AUTHOR
Henry Bottomley, May 22 2000
STATUS
approved