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A242555 Least number k such that k^32+n^32 is prime. 1
1, 29, 40, 33, 34, 131, 50, 9, 8, 11, 10, 13, 12, 97, 166, 221, 200, 13, 10, 61, 176, 23, 22, 65, 94, 151, 352, 87, 2, 1, 38, 39, 4, 5, 48, 137, 18, 11, 4, 3, 60, 55, 40, 9, 106, 33, 10, 29, 134, 7, 44, 33, 50, 1, 38, 5, 148, 37, 2, 41, 10, 11, 94, 75, 4, 5, 100, 5, 22 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

If a(n) = 1, then n is in A006315.

LINKS

Table of n, a(n) for n=1..69.

MATHEMATICA

lnk[n_]:=Module[{k=1, n32=n^32}, While[!PrimeQ[n32+k^32], k++]; k]; Array[ lnk, 70] (* Harvey P. Dale, Apr 26 2018 *)

PROG

(Python)

import sympy

from sympy import isprime

def a(n):

..for k in range(10**4):

....if isprime(n**32+k**32):

......return k

n = 1

while n < 100:

..print(a(n))

..n += 1

(PARI) a(n)=for(k=1, 10^3, if(ispseudoprime(n^32+k^32), return(k)));

n=1; while(n<100, print(a(n)); n+=1)

CROSSREFS

Cf. A069003, A006315.

Sequence in context: A159888 A159887 A108325 * A101007 A253252 A155575

Adjacent sequences:  A242552 A242553 A242554 * A242556 A242557 A242558

KEYWORD

nonn

AUTHOR

Derek Orr, May 17 2014

STATUS

approved

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Last modified June 12 08:13 EDT 2021. Contains 344943 sequences. (Running on oeis4.)