A137471 Positive numbers n such that n^3 +- (n+1) are primes.

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

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

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

Adjacent sequences: A137468 A137469 A137470 * A137472 A137473 A137474

Keyword

nonn,easy

Author

Vladimir Joseph Stephan Orlovsky, Apr 21 2008

Extensions

More terms from Stefan Steinerberger and Emeric Deutsch, Apr 26 2008

Status

approved