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A155929 Integers a(n) such that cube(n)-square(n)-1 and cube(n)+square(n)+1 are primes. 3
2, 3, 9, 12, 30, 57, 66, 87, 111, 120, 195, 243, 246, 279, 378, 381, 432, 450, 471, 480, 597, 651, 759, 810, 933, 987, 1053, 1356, 1362, 1404, 1407, 1410, 1548, 1563, 1638, 1752, 1758, 1998, 2016, 2115, 2157, 2259, 2280, 2385, 2499, 2607, 2775, 2817, 2826 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

2^3-2^2-1=3;2^3+2^2+1=13, 3^3-3^2-1=17;3^3+3^2+1=37, ...

LINKS

Table of n, a(n) for n=1..49.

MATHEMATICA

lst={}; Do[c=n^3; s=n^2; p1=c-s-1; p2=c+s+1; If[PrimeQ[p1]&&PrimeQ[p2], AppendTo[lst, n]], {n, 7!}]; lst

CROSSREFS

Sequence in context: A057017 A239859 A047162 * A175206 A032486 A123859

Adjacent sequences:  A155926 A155927 A155928 * A155930 A155931 A155932

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, Jan 30 2009

STATUS

approved

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Last modified October 14 09:25 EDT 2019. Contains 327995 sequences. (Running on oeis4.)