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A250842
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Primes of the form 5^x + y^5 with x, y > 0.
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2
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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
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OFFSET
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1,1
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LINKS
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EXAMPLE
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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.
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MAPLE
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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:
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MATHEMATICA
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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]
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CROSSREFS
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Cf. similar sequences listed in A250481.
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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