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A130135
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Numbers k such that prime(k^3) - k is prime.
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1
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2, 4, 12, 30, 40, 42, 62, 66, 70, 72, 84, 88, 98, 112, 130, 150, 180, 248, 264, 298, 336, 342, 354, 408, 438, 450, 468, 482, 486, 546, 550, 558
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OFFSET
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1,1
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LINKS
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Table of n, a(n) for n=1..32.
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EXAMPLE
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a(1)=2 because prime(2^3)-2 = 19-2 = 17 and 17 is prime,
a(2)=4 because prime(4^3)-4 = 311-4 = 307 and 307 is prime,
a(3)=12 because prime(12^3)-12 = 14741 and 14741 is prime, ...
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MAPLE
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ts_pra_3:=proc(n) local i, ans; ans := [ ]: for i from 1 to n do if (isprime(ithprime(i^(3))-i)) then ans := [ op(ans), i ]: fi: od; RETURN(ans) end: ts_pra_3(200);
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PROG
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(PARI) is(k) = isprime(prime(k^3)-k); \\ Jinyuan Wang, Apr 10 2020
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CROSSREFS
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Cf. A064269 (prime(k) - k is prime), A105962 (prime(k^2) - k is prime).
Sequence in context: A148184 A148185 A215871 * A048618 A083554 A059412
Adjacent sequences: A130132 A130133 A130134 * A130136 A130137 A130138
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KEYWORD
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nonn,more,less
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AUTHOR
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Jani Melik, Aug 01 2007
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EXTENSIONS
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a(18)-a(32) from Jinyuan Wang, Apr 10 2020
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STATUS
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approved
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