A193423 Primes of the form x^2+y^3 with x, y and y^3 - x^2 >= 0.

2, 31, 43, 73, 89, 113, 241, 337, 347, 359, 379, 443, 487, 521, 593, 599, 733, 829, 953, 1009, 1049, 1129, 1213, 1289, 1361, 1367, 1753, 1777, 1907, 2017, 2089, 2213, 2297, 2341, 2393, 2521, 2689, 2753, 2953, 2969, 3221, 3391, 3571, 3631, 3797, 3833, 4051, 4133, 4159, 4177, 4217, 4457, 4721, 4937, 5237, 5813

Offset

1,1

Comments

Subsequence of A066649.

Links

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

Example

2 is in the sequence because 2 is prime, 2=1^2+1^3 and 1^3-1^2=0;
31 is in the sequence because 31 is prime, 31=2^2+3^3 and 3^3-2^2>0;
43 is in the sequence because 43 is prime, 43=4^2+3^3 and 3^3-4^2>0;

Prog

(PARI) list(lim)=my(v=List(), t, B); lim\=1; for(b=1, sqrtn(lim+.5, 3), B=b^3; for(a=1, min(lim-B, sqrtint(B)), if(isprime(t=B+a^2), listput(v, t)))); vecsort(Vec(v), , 8) \\ Charles R Greathouse IV, Aug 28 2011

Crossrefs

Sequence in context: A120638 A101017 A207973 * A241484 A235477 A370157

Adjacent sequences: A193420 A193421 A193422 * A193424 A193425 A193426

Keyword

nonn

Author

Juri-Stepan Gerasimov, Aug 27 2011

Extensions

Corrected by D. S. McNeil, Aug 27 2011

Status

approved