A250716 Primes of the form 3^x + y^3 with x, y >0.

11, 17, 67, 73, 89, 251, 307, 521, 593, 1009, 2251, 2699, 2753, 3187, 4099, 4177, 4339, 4931, 6569, 7561, 8009, 8081, 8243, 10651, 10657, 10729, 10891, 14561, 17209, 17579, 17657, 19763, 21961, 24137, 28513, 32771, 39313, 41491, 54881, 57059, 59113

Offset: 1

Author

Vincenzo Librandi, Nov 27 2014

Keywords

• nonn

Examples

			67 is in this sequence because 67 is prime and 3^1+4^3 = 67.
521 is in this sequence because 521 is prime and 3^2+8^3 = 521.
		

Crossrefs

Cf. A250481, A250483.

Programs

Mathematica

f[x_, y_]:= 3^x+y^3; lst={}; Do[p=f[x, y]; If[PrimeQ[p], AppendTo[lst, p]], {y, 50}, {x, 50}];Take[Union[lst], 50]