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A130474 Prime numbers p of the form p=x^2+y^3 such that q =A130475(n)= abs(x^2-y^3) is prime and smaller than p. 1

%I #2 Sep 24 2013 09:24:40

%S 5,31,43,89,127,241,269,283,379,449,449,487,521,593,811,919,953,1009,

%T 1051,1601,2017,2089,2089,2143,2341,2521,2521,2609,2731,2953,3041,

%U 3163,3391,3631,3943,4051,4129,4159,4481,4481,4651,4931,4969,5113,5209,5309

%N Prime numbers p of the form p=x^2+y^3 such that q =A130475(n)= abs(x^2-y^3) is prime and smaller than p.

%F a(n)= x^2+y^3 and A130475(n)=q=abs(x^2-y^3); a(n) > A130475(n);a(n) and A130475(n) are in A000040 (prime numbers)

%e a(4)= 89 because 89= 9^2+2^3= 81 + 8 and A130475(4)= 73 =abs(9^2-2^3)= abs(81-8) ; A130475(4) < a(4) ; A130475(4) and a(4) are prime numbers, members of A000040.

%e a(5)= 127 because 127= 10^2+ 3^3= 100 + 27 and A130475(5)= 73 = abs(10^2-3^3)= abs(100-27) ; A130475(5) < a(5) ; A130475(5) and a(5) are prime numbers, members of A000040.

%e a(9)= 379 because 379= 6^2 + 7^3= 36 + 343 and A130475(9)= 307 = abs(6^2-7^3)= abs(36-343) ; A130475(9) < a(9) ; A130475(9) and a(9) are prime numbers, members of A000040.

%Y Cf. A000040; A130475.

%K easy,nonn

%O 1,1

%A _Tomas Xordan_, May 28 2007

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Last modified April 24 22:17 EDT 2024. Contains 371964 sequences. (Running on oeis4.)