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A244949 Least number k > n such that k^64 + n^64 is prime.

%I A244949 #11 May 22 2025 10:21:39
%S A244949 102,37,32,39,118,13,16,11,154,41,94,29,158,17,64,291,70,107,66,63,58,
%T A244949 87,38,397,282,69,32,129,142,67,210,87,200,227,82,55,70,137,388,541,
%U A244949 140,103,64,167,286,71,60,593,262,459,62,69,92,91,128,81,98,149,164,107,192,103
%N A244949 Least number k > n such that k^64 + n^64 is prime.
%C A244949 a(n) = n+1 iff n is in A174157.
%H A244949 Jens Kruse Andersen, <a href="/A244949/b244949.txt">Table of n, a(n) for n = 1..10000</a>
%e A244949 8^64 + 11^64 = 4457915690803004131256192897205630962697827851093882159977969339137 is prime. Since 8^64 + 10^64 and 8^64 + 9^64 are both composite, a(8) = 11.
%o A244949 (Python)
%o A244949 import sympy
%o A244949 from sympy import isprime
%o A244949 def a(n):
%o A244949   for k in range(n+1,10**4):
%o A244949     if isprime(k**64+n**64):
%o A244949       return k
%o A244949 n = 1
%o A244949 while n < 100:
%o A244949   print(a(n),end=', ')
%o A244949   n += 1
%o A244949 (PARI) a(n)=for(k=n+1,10^4,if(isprime(k^64+n^64),return(k)))
%o A244949 n=1;while(n<100,print1(a(n),", ");n++)
%Y A244949 Cf. A158979, A089489, A242556.
%K A244949 nonn
%O A244949 1,1
%A A244949 _Derek Orr_, Jul 08 2014