OFFSET
1,1
COMMENTS
The sequence is infinite.
LINKS
Robert Israel, Table of n, a(n) for n = 1..986
MAPLE
A076600:= proc(n) local q;
q:= max(select(t -> n^2/t - t > 2*n and (t - n^2/t)::even, numtheory:-divisors(n^2)));
if q = -infinity then 0 else (n^2/q - q)/2 fi;
end proc:
A[1]:= 11;
for n from 2 to 100 do
A[n]:= A076600(A[n-1]);
od:
seq(A[i], i=1..100); # Robert Israel, Mar 22 2018
MATHEMATICA
nmax = 100;
A076600[n_] := Module[{q},
q = Max[Select[Divisors[n^2], n^2/# - # > 2n &&
EvenQ[# - n^2/#]&]];
If[q == -Infinity, 0, (n^2/q - q)/2]];
a[1] = 11;
For[n = 2, n <= nmax, n++, a[n] = A076600[a[n - 1]]];
Table[a[n], {n, 1, nmax}] (* Jean-François Alcover, May 17 2023, after Robert Israel *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Zak Seidov, Oct 25 2002
STATUS
approved