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A217718
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Primes of the form x^3 + y^3 - 1, where x and y are primes.
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2
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53, 151, 467, 2539, 3527, 6983, 7109, 30133, 31121, 31247, 34703, 41957, 50777, 59581, 62819, 68947, 69263, 75041, 79631, 81703, 91673, 98711, 106019, 109297, 110681, 159013, 183329, 205721, 228311, 228383, 231893, 239147, 256031, 256771, 295901, 302959, 312929
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OFFSET
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1,1
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COMMENTS
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A number is in this sequence if it is prime, and can be expressed as p1^3 + p2^3 - 1, where p1 and p2 are also prime.
There are 175 numbers in the sequence < 10^7: a(175) = 83^3 + 211^3 - 1 = 9965717.
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LINKS
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Christian N. K. Anderson, Table of n, a(n) for n = 1..1890
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EXAMPLE
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3527 is in the sequence, because 11^3 + 13^3 - 1 = 3527, and 11, 13, and 3527 are all prime.
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MATHEMATICA
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mx = 25; Union[Select[Flatten[Table[Prime[a]^3 + Prime[b]^3 - 1, {a, mx}, {b, a, mx}]], # < Prime[mx]^3 && PrimeQ[#] &]] (* T. D. Noe, Mar 29 2013 *)
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CROSSREFS
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Cf. A024670 (sum of two cubes).
Cf. A214175 (primes that are one more than the sum of two prime cubes).
Sequence in context: A142043 A175600 A142417 * A044385 A044766 A342450
Adjacent sequences: A217715 A217716 A217717 * A217719 A217720 A217721
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KEYWORD
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nonn
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AUTHOR
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Kevin L. Schwartz and Christian N. K. Anderson, Mar 21 2013
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STATUS
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approved
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