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A217718 Primes of the form x^3 + y^3 - 1, where x and y are primes. 2

%I #20 Apr 23 2013 11:13:41

%S 53,151,467,2539,3527,6983,7109,30133,31121,31247,34703,41957,50777,

%T 59581,62819,68947,69263,75041,79631,81703,91673,98711,106019,109297,

%U 110681,159013,183329,205721,228311,228383,231893,239147,256031,256771,295901,302959,312929

%N Primes of the form x^3 + y^3 - 1, where x and y are primes.

%C 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.

%C There are 175 numbers in the sequence < 10^7: a(175) = 83^3 + 211^3 - 1 = 9965717.

%H Christian N. K. Anderson, <a href="/A217718/b217718.txt">Table of n, a(n) for n = 1..1890</a>

%e 3527 is in the sequence, because 11^3 + 13^3 - 1 = 3527, and 11, 13, and 3527 are all prime.

%t 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 *)

%Y Cf. A024670 (sum of two cubes).

%Y Cf. A214175 (primes that are one more than the sum of two prime cubes).

%K nonn

%O 1,1

%A _Kevin L. Schwartz_ and _Christian N. K. Anderson_, Mar 21 2013

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Last modified April 23 03:30 EDT 2024. Contains 371906 sequences. (Running on oeis4.)