The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A242554 Least number k such that n^16+k^16 is prime. 1
 1, 1, 4, 3, 6, 5, 6, 7, 22, 13, 16, 5, 8, 5, 14, 11, 10, 7, 16, 31, 8, 9, 10, 11, 38, 29, 10, 9, 22, 61, 20, 5, 4, 3, 16, 11, 6, 25, 28, 7, 6, 17, 16, 1, 46, 9, 58, 61, 22, 41, 92, 3, 14, 19, 14, 23, 56, 37, 20, 109, 6, 121, 10, 39, 4, 67, 34, 11, 26, 9, 30, 11, 12, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS If a(n) = 1, then n is in A006313. LINKS Table of n, a(n) for n=1..74. EXAMPLE 4^16+1^16 = 4294967297 is not prime. 4^16+2^16 = 4295032832 is not prime. 4^16+3^16 = 4338014017 is prime. Thus, a(4) = 3. PROG (Python) import sympy from sympy import isprime def a(n): ..for k in range(10**4): ....if isprime(n**16+k**16): ......return k n = 1 while n < 100: ..print(a(n)) ..n += 1 (PARI) a(n)=for(k=1, 10^3, if(ispseudoprime(n^16+k^16), return(k))); n=1; while(n<100, print(a(n)); n+=1) CROSSREFS Cf. A069003, A006313. Sequence in context: A024602 A367269 A131603 * A219176 A251739 A224715 Adjacent sequences: A242551 A242552 A242553 * A242555 A242556 A242557 KEYWORD nonn AUTHOR Derek Orr, May 17 2014 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified April 16 17:36 EDT 2024. Contains 371749 sequences. (Running on oeis4.)