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A137471
Positive numbers n such that n^3 +- (n+1) are primes.
1
2, 3, 8, 9, 15, 18, 21, 29, 41, 48, 60, 69, 71, 104, 108, 126, 155, 168, 186, 191, 221, 239, 261, 276, 360, 366, 381, 414, 428, 429, 480, 518, 570, 630, 701, 749, 755, 825, 836, 879, 1140, 1170, 1173, 1220, 1290, 1395, 1449, 1455, 1466, 1485, 1605, 1611, 1655
OFFSET
1,1
LINKS
EXAMPLE
2^3 +- 3 -> (5, 11) (primes);
3^3 +- 4 -> (23, 31) (primes).
MAPLE
a:=proc(n) if isprime(n^3+n+1)=true and isprime(n^3-n-1)=true then n else end if end proc: seq(a(n), n=1..1200); # Emeric Deutsch, Apr 29 2008
MATHEMATICA
Select[Range[900], PrimeQ[ #^3-(#+1)]&&PrimeQ[ #^3+(#+1)]&]
CROSSREFS
Sequence in context: A246396 A054462 A101471 * A051209 A332481 A331821
KEYWORD
nonn,easy
AUTHOR
EXTENSIONS
More terms from Stefan Steinerberger and Emeric Deutsch, Apr 26 2008
STATUS
approved