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A242556
Least number k such that k^64+n^64 is prime.
1
1, 37, 32, 39, 118, 13, 16, 11, 154, 41, 8, 29, 6, 17, 64, 7, 14, 107, 66, 63, 58, 87, 38, 397, 282, 69, 32, 129, 12, 67, 210, 3, 200, 227, 82, 55, 2, 7, 4, 541, 10, 103, 64, 167, 286, 71, 60, 593, 6, 459, 14, 3, 2, 91, 4, 81, 98, 21, 164, 47, 36, 51, 10, 15, 84, 19, 30
OFFSET
1,2
COMMENTS
If a(n) = 1, then n is in A006316.
MATHEMATICA
lnk[n_]:=Module[{c=n^64, k=1}, While[!PrimeQ[c+k^64], k++]; k]; Array[lnk, 70] (* Harvey P. Dale, Oct 21 2017 *)
PROG
(Python)
import sympy
from sympy import isprime
def a(n):
..for k in range(10**4):
....if isprime(n**64+k**64):
......return k
n = 1
while n < 100:
..print(a(n))
..n += 1
(PARI) a(n)=for(k=1, 10^3, if(ispseudoprime(n^64+k^64), return(k)));
n=1; while(n<100, print(a(n)); n+=1)
CROSSREFS
Sequence in context: A075400 A222293 A350002 * A087366 A324249 A022993
KEYWORD
nonn
AUTHOR
Derek Orr, May 17 2014
STATUS
approved