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A130475
Prime numbers q of the form q=abs(x^2-y^3) such that p =A130474(n)= x^2+y^3 is prime and greater than q. (Prime numbers arising from A130474).
1
3, 23, 11, 73, 73, 191, 19, 229, 307, 199, 433, 199, 503, 431, 757, 233, 71, 991, 997, 577, 1439, 1367, 89, 2089, 2053, 1873, 521, 2593, 2677, 503, 2791, 3109, 3359, 3119, 3257, 2699, 673, 2591, 3457, 4231, 4597, 2269, 2969, 719, 1753, 5059, 1993, 5449
OFFSET
1,1
FORMULA
a(n)= abs(x^2-y^3) and A130474(n)=p=x^2+y^3; a(n) < A130474(n); a(n) and A130474(n) are in A000040 (prime numbers)
EXAMPLE
a(4)= 73 because 73= abs(9^2-2^3)= abs(81 - 8 ) and A130474(4)= 89 =9^2+2^3= 81+8 ; A130474(4) > a(4) ; A130474(4) and a(4) are prime numbers, members of A000040.
a(5)= 73 because 73=abs(10^2-3^3)= abs(100 - 27) and A130474(5)= 127 = 10^2+3^3= 100+27 ; A130474(5) > a(5) ; A130474(5) and a(5) are prime numbers, members of A000040.
a(9)= 307 because 307= abs(6^2 - 7^3)=abs(36 - 343) and A130474(9)= 379 = 6^2+7^3= 36+343 ; A130474(9) > a(9) ; A130474(9) and a(9) are prime numbers, members of A000040.
CROSSREFS
Sequence in context: A088605 A272816 A063562 * A212998 A157819 A122902
KEYWORD
easy,nonn
AUTHOR
Tomas Xordan, May 28 2007
STATUS
approved