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A085366 Semiprimes that are the sum of two positive cubes. Common terms of A003325 and A046315. 5
9, 35, 65, 91, 133, 217, 341, 407, 559, 737, 793, 1027, 1241, 1339, 1343, 1843, 1853, 2071, 2413, 2771, 2869, 3197, 3383, 3439, 3473, 4097, 4439, 5129, 5833, 6119, 6641, 7471, 7859, 8027, 8587, 9773, 10261, 10649, 10991, 11377, 12679, 12913, 14023 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Sum of two positive cubes x^3+y^3 such that both x+y and x^2-x*y+y^2 are primes.

The only square is 9. Also, all terms have a unique representation as a sum of two distinct positive cubes. [Zak Seidov, Jun 02 2011]

LINKS

Zak Seidov, Table of n, a(n) for n=1..1356

EXAMPLE

a(2)=35 because 3^3+2^3=5*7, a(5)=133=5^3+2^3=(5+2)*(5^2-5*2+2^2)=7*19.

CROSSREFS

Cf. A003325, A046388, A001358, A085367.

Sequence in context: A265377 A187554 A267702 * A173245 A033566 A226755

Adjacent sequences:  A085363 A085364 A085365 * A085367 A085368 A085369

KEYWORD

nonn

AUTHOR

Hugo Pfoertner, Jun 25 2003

STATUS

approved

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Last modified June 28 20:39 EDT 2017. Contains 288840 sequences.