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A204919 a(n) = q^2 where q is the least prime such that n divides A204916(n)^2 - q^2.

%I A204919 #10 May 05 2019 04:31:37
%S A204919 4,9,4,9,4,25,4,9,4,9,4,25,4,9,4,9,4,49,4,9,4,25,289,25,4,49,4,9,4,49,
%T A204919 4,25,4,121,9,49,961,49,4,9,4,121,4,25,4,289,1681,25,4,361,4,49,2209,
%U A204919 529,4,9,4,289,4,49
%N A204919 a(n) = q^2 where q is the least prime such that n divides A204916(n)^2 - q^2.
%C A204919 For a guide to related sequences, see A204892.
%C A204919 Original name was "Least prime q^2 such that n divides p^2-q^2 for some prime p>q", which would be A089090. - _Robert Israel_, May 04 2019
%H A204919 Robert Israel, <a href="/A204919/b204919.txt">Table of n, a(n) for n = 1..10000</a>
%p A204919 N:= 100: # to get a(1)..a(N)
%p A204919 A:= Vector(N): count:= 0:
%p A204919 p:= 2: P:= 2:
%p A204919 for i from 1 while count < N do
%p A204919   p:= nextprime(p);
%p A204919   ps:= p^2;
%p A204919   P:= P, p;
%p A204919   for j from 1 to i while count < N do
%p A204919    qs:= P[j]^2;
%p A204919    S:= convert(select(t -> t <= N and A[t]=0, numtheory:-divisors(ps-qs)),list);
%p A204919    A[S]:= qs;
%p A204919    count:= count + nops(S);
%p A204919 od od:
%p A204919 convert(A,list); # _Robert Israel_, May 04 2019
%t A204919 (See the program at A204916.)
%Y A204919 Cf. A089090, A204916, A204908, A204900, A204892.
%K A204919 nonn
%O A204919 1,1
%A A204919 _Clark Kimberling_, Jan 20 2012
%E A204919 Name corrected by _Robert Israel_, May 04 2019