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A281549 Numbers n such that abs(n - 4^k) is prime for k = 1..10. 1
525, 635, 3335, 22547, 132725, 242073, 590663, 598793, 795143, 963815, 1910433, 2506647, 5833497, 13032533, 13336685, 22163097, 22291055, 27730755, 36069767, 39412953, 41006745, 42520623, 44594457, 47869577, 63735185, 73770483, 76852937, 89703543, 100998105 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
EXAMPLE
For n = 525, the primes are {521, 509, 461, 269, 499, 3571, 15859, 65011, 261619, 1048051}.
MATHEMATICA
AA = Table[PrimeQ[Abs[n - 4^k]], {n, 1, 150000}, {k, 1, 10}];
Flatten[Position[AA, {True, True, True, True, True, True, True, True, True, True}]]
PROG
(PARI) is(n)=for(k=1, 10, if(!isprime(abs(n-4^k)), return(0))); 1
CROSSREFS
Cf. A281047.
Sequence in context: A249286 A283345 A125012 * A308242 A260606 A181112
KEYWORD
nonn
AUTHOR
EXTENSIONS
Extended by Charles R Greathouse IV, Jan 24 2017
a(25)-a(29) from Chai Wah Wu, Jan 25 2017
STATUS
approved

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Last modified April 25 12:33 EDT 2024. Contains 371969 sequences. (Running on oeis4.)