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A250842 Primes of the form 5^x + y^5 with x, y > 0. 2
37, 157, 1049, 7901, 16649, 78157, 615949, 1048601, 1049201, 1064201, 1890193, 1953157, 1960901, 2201957, 9915749, 17210393, 45435449, 48860893, 60466181, 79235293, 79313293, 81188293, 82382557, 130691237, 130691357, 130769357, 205963001, 205963601 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

EXAMPLE

37 is in this sequence because 37 is prime and 5^1+2^5 = 37.

7901 is in this sequence because 7901 is prime and 5^3+6^5 = 7901.

MAPLE

N:= 10^10: # for terms <= N

Res:= NULL:

for x from 1 to floor(log[5](N)) do

  for y from 2 by 2 do

     z:= y^5 + 5^x;

     if z > N then break fi;

     if isprime(z) then Res:= Res, z fi

od od:

sort([Res]); # Robert Israel, Dec 16 2019

MATHEMATICA

f[x_, y_]:= 5^x + y^5; lst={}; Do[p=f[x, y]; If[PrimeQ[p], AppendTo[lst, p]], {y, 50}, {x, 50}]; Take[Union[lst], 50]

CROSSREFS

Cf. A250546.

Cf. similar sequences listed in A250481.

Sequence in context: A142197 A140011 A296156 * A083389 A142909 A269259

Adjacent sequences:  A250839 A250840 A250841 * A250843 A250844 A250845

KEYWORD

nonn

AUTHOR

Vincenzo Librandi, Nov 29 2014

STATUS

approved

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Last modified July 14 06:34 EDT 2020. Contains 335716 sequences. (Running on oeis4.)