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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
5, 31, 43, 89, 127, 241, 269, 283, 379, 449, 449, 487, 521, 593, 811, 919, 953, 1009, 1051, 1601, 2017, 2089, 2089, 2143, 2341, 2521, 2521, 2609, 2731, 2953, 3041, 3163, 3391, 3631, 3943, 4051, 4129, 4159, 4481, 4481, 4651, 4931, 4969, 5113, 5209, 5309 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..46.

FORMULA

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)

EXAMPLE

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.

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.

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.

CROSSREFS

Cf. A000040; A130475.

Sequence in context: A341632 A287300 A162665 * A238674 A245523 A147033

Adjacent sequences:  A130471 A130472 A130473 * A130475 A130476 A130477

KEYWORD

easy,nonn

AUTHOR

Tomas Xordan, May 28 2007

STATUS

approved

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Last modified June 13 06:07 EDT 2021. Contains 344981 sequences. (Running on oeis4.)