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A163742 Prime pairs (p,q) of the form p=A002315(k), q=A001653(k) for some k. +0
2
7, 5, 41, 29, 63018038201, 44560482149, 19175002942688032928599, 13558774610046711780701 (list; graph; listen)
OFFSET

1,1

COMMENT

By construction, all these pairs fulfill p^2 -2*q^2 = -1.

One can generate the combined A002315 and A001653 by a mixed recursion 3p+4q -> p; 2p+3q -> q, and then test after each step both p and q for primality.

EXAMPLE

(A002315(1),A001653(1)) = (7,5) are both prime and define the first pair in the sequence.

(A002315(2),A001653(2)) = (41,29) are both prime and define the second pair in the sequence.

(A002315(3),A001653(3)) = (239,169=13^2) contain the composite 169 and do not contribute to the sequence.

CROSSREFS

Cf. A086397, A118612.

Sequence in context: A070426 A142883 A146382 this_sequence A089244 A063003 A038271

Adjacent sequences: A163739 A163740 A163741 this_sequence A163743 A163744 A163745

KEYWORD

nonn,less

AUTHOR

Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Aug 03 2009

EXTENSIONS

Definition clarified by R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Aug 12 2009

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Last modified November 27 14:17 EST 2009. Contains 167569 sequences.


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