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A204911 The prime q>=5 such that n divides p-q, where p>q is the least prime for which such a prime q exists.

%I A204911 #17 Jun 25 2024 11:24:51
%S A204911 5,5,5,7,7,5,5,5,5,7,7,5,5,5,7,7,7,5,5,11,5,7,7,5,11,5,5,13,13,7,5,5,
%T A204911 5,7,13,5,5,5,5,7,7,5,11,17,7,7,7,5,5,11,5,7,7,5,17,5,13,13,13,7,5,5,
%U A204911 5,7,7,5,5,5,11,13,7,7,5,5,7,7,13,5,5,17,5,7,7,5,11,11,5,13,13,7,11,5,5
%N A204911 The prime q>=5 such that n divides p-q, where p>q is the least prime for which such a prime q exists.
%C A204911 For a guide to related sequences, see A204892.
%H A204911 Robert Israel, <a href="/A204911/b204911.txt">Table of n, a(n) for n = 1..10000</a>
%p A204911 f:= proc(n) local V,q,r;
%p A204911   V:= Array(0..n-1); q:= 4;
%p A204911   do
%p A204911    q:= nextprime(q);
%p A204911    r:= q mod n;
%p A204911    if V[r] = 0 then V[r]:= q
%p A204911    else return V[r]
%p A204911    fi
%p A204911   od
%p A204911 end proc:
%p A204911 map(f, [$1..100]); # _Robert Israel_, Jul 24 2018
%t A204911 (See the program at A204908.)
%o A204911 (Python)
%o A204911 from sympy import nextprime
%o A204911 def a(n):
%o A204911     V, q = [0 for _ in range(n)], 4
%o A204911     while True:
%o A204911         q = nextprime(q)
%o A204911         r = q%n
%o A204911         if V[r] == 0: V[r] = q
%o A204911         else: return int(V[r])
%o A204911 print([a(n) for n in range(1, 94)]) # _Michael S. Branicky_, Jun 25 2024 after _Robert Israel_
%Y A204911 Cf. A204908, A204900, A204892.
%K A204911 nonn
%O A204911 1,1
%A A204911 _Clark Kimberling_, Jan 20 2012
%E A204911 More terms from _Robert G. Wilson v_, Jul 24 2018