OFFSET
1,5
LINKS
David A. Corneth, Table of n, a(n) for n = 1..10000
EXAMPLE
a(5) = 3 as the right triangle with sides (3, 4, 5) has hypotenuse n = 5 smallest side a(5) = 3. This is the smallest side a right triangle with integer sides and hypotenuse 5 can have. - David A. Corneth, Apr 10 2021
MATHEMATICA
f[n_]:=Block[{k=n-1, m=Sqrt[n/2], a}, While[k>m&&!IntegerQ[(a=Sqrt[n^2-k^2])], k--]; If[k<=m, 0, a]]; Table[f[n], {n, 90}]
PROG
(PARI) first(n) = {my(lh = List(), res = vector(n, i, oo)); for(u = 2, sqrtint(n), for(v = 1, u, if (u^2+v^2 > n, break); if ((gcd(u, v) == 1) && (0 != (u-v)%2), for (i = 1, n, if (i*(u^2+v^2) > n, break); listput(lh, i*(u^2+v^2)); res[i*(u^2+v^2)] = vecmin([res[i*(u^2+v^2)], i*(u^2 - v^2), i*2*u*v]))))); for(i = 1, n, if(res[i] == oo, res[i] = 0)); res } \\ David A. Corneth, Apr 10 2021, adapted from A009000
CROSSREFS
KEYWORD
nonn
AUTHOR
Sébastien Dumortier, Jun 20 2005
EXTENSIONS
Extended by Ray Chandler, Dec 20 2011
STATUS
approved