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A086121 Positive sums or differences of two cubes of primes. 3
16, 19, 35, 54, 98, 117, 133, 152, 218, 250, 316, 335, 351, 370, 468, 686, 866, 988, 1206, 1304, 1323, 1339, 1358, 1456, 1674, 1854, 1946, 2072, 2170, 2189, 2205, 2224, 2322, 2540, 2662, 2716, 3528, 3582, 4394, 4570, 4662, 4788, 4886, 4905, 4921, 4940, 5038 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Hans Havermann and T. D. Noe, Table of n, a(n) for n=1,...,20000.

EXAMPLE

117 and 133 each belong to the (set) sequence because can be written as 117 = 5^3 - 2^3 and 133 = 5^3 + 2^3.

MATHEMATICA

nn=10^6; td=Reap[Do[n=Prime[i]^3-Prime[j]^3; If[n<=nn, Sow[n]], {i, PrimePi[Sqrt[nn/6]]}, {j, i-1}]][[2, 1]]; ts=Reap[Do[n=Prime[i]^3+Prime[j]^3; If[n<=nn, Sow[n]], {i, PrimePi[nn^(1/3)]}, {j, i}]][[2, 1]]; Union[td, ts] [From T. D. Noe, Oct 04 2010]

n = 100; Select[Sort@Flatten@ Table[Prime[i]^3 + (-1)^k Prime[j]^3, {i, n}, {j, i}, {k, 2}], 0 < # < (Prime[n] + 2)^3 - Prime[n]^3 &] - Ray Chandler, Oct 05 2010

CROSSREFS

Cf. A086119, A086120. Also see A045636, A045699.

Sequence in context: A249612 A260560 A034012 * A030402 A061934 A195683

Adjacent sequences:  A086118 A086119 A086120 * A086122 A086123 A086124

KEYWORD

nonn

AUTHOR

Hollie L. Buchanan II, Jul 11 2003

EXTENSIONS

Edited by N. J. A. Sloane, Oct 05 2010 to remove a discrepancy between the terms of the sequence and the b-file. The old Mma program and b-file were wrong.

STATUS

approved

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Last modified May 24 02:13 EDT 2017. Contains 286937 sequences.