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A244948 Least number k > n such that k^32 + n^32 is prime.

%I A244948 #11 May 22 2025 10:21:39
%S A244948 30,29,40,33,34,131,50,9,44,11,38,13,18,97,166,221,200,37,82,61,176,
%T A244948 23,102,65,94,151,352,87,38,37,38,39,46,37,48,137,54,55,68,43,60,55,
%U A244948 146,51,106,87,82,65,134,53,106,103,90,71,96,71,148,91,94,139,74,69,94,75,86,169,100
%N A244948 Least number k > n such that k^32 + n^32 is prime.
%C A244948 a(n) = n+1 iff n is in A174156.
%H A244948 Jens Kruse Andersen, <a href="/A244948/b244948.txt">Table of n, a(n) for n = 1..10000</a>
%e A244948 34^32 + 35^32 = 35884563485651241417769982593434627193100364196481 is not prime. 34^2 + 36^32 = 2^32*(17^32+18^32) is not prime. 34^32 + 37^32 = 162384303092765940334383766635859112907663593431937 is prime. Thus a(34) = 37.
%o A244948 (Python)
%o A244948 import sympy
%o A244948 from sympy import isprime
%o A244948 def a(n):
%o A244948   for k in range(n+1,10**4):
%o A244948     if isprime(k**32+n**32):
%o A244948       return k
%o A244948 n = 1
%o A244948 while n < 100:
%o A244948   print(a(n),end=', ')
%o A244948   n += 1
%o A244948 (PARI) a(n)=for(k=n+1,10^4,if(isprime(k^32+n^32),return(k)))
%o A244948 n=1;while(n<100,print1(a(n),", ");n++)
%Y A244948 Cf. A158979, A089489, A242555.
%K A244948 nonn
%O A244948 1,1
%A A244948 _Derek Orr_, Jul 08 2014