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A155931 Squares s(n) such that cube(n)-square(n)-1 and cube(n)+square(n)+1 are primes. 1
4, 9, 81, 144, 900, 3249, 4356, 7569, 12321, 14400, 38025, 59049, 60516, 77841, 142884, 145161, 186624, 202500, 221841, 230400, 356409, 423801, 576081, 656100, 870489, 974169, 1108809, 1838736, 1855044, 1971216, 1979649, 1988100, 2396304 (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..33.

MATHEMATICA

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

CROSSREFS

Cf. A155929, A155930

Sequence in context: A041030 A061104 A082381 * A309801 A248245 A077530

Adjacent sequences:  A155928 A155929 A155930 * A155932 A155933 A155934

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, Jan 30 2009

STATUS

approved

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Last modified October 16 03:37 EDT 2019. Contains 328040 sequences. (Running on oeis4.)