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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
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
#^2&/@Select[Range[1600], AllTrue[#^3+{-#^2-1, #^2+1}, PrimeQ]&] (* Harvey P. Dale, Feb 24 2023 *)
CROSSREFS
Sequence in context: A359654 A061104 A082381 * A309801 A248245 A368629
KEYWORD
nonn
AUTHOR
STATUS
approved

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Last modified April 25 08:27 EDT 2024. Contains 371964 sequences. (Running on oeis4.)