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A138420
a(n) = ((prime(n))^4-(prime(n))^2)/4.
5
3, 18, 150, 588, 3630, 7098, 20808, 32490, 69828, 176610, 230640, 468198, 706020, 854238, 1219368, 1971918, 3028470, 3460530, 5036658, 6351660, 7098228, 9735960, 11862858, 15683580, 22129968, 26012550, 28135068, 32767038, 35286570
OFFSET
1,1
COMMENTS
Number of monic irreducible polynomials of degree 4 over GF(prime(n)). - Robert Israel, Jan 07 2015
LINKS
FORMULA
a(n) = A138402(n)/4. - R. J. Mathar, Oct 15 2017
MAPLE
seq(1/4*(ithprime(i)^4 - ithprime(i)^2), i=1..100); # Robert Israel, Jan 07 2015
MATHEMATICA
a = {}; Do[p = Prime[n]; AppendTo[a, (p^4 - p^2)/4], {n, 1, 50}]; a
PROG
(Magma) [(NthPrime((n))^4 - NthPrime((n))^2)/4: n in [1..30] ]; // Vincenzo Librandi, Jun 17 2011
(PARI) forprime(p=2, 1e3, print1((p^4-p^2)/4", ")) \\ Charles R Greathouse IV, Jul 15 2011
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Artur Jasinski, Mar 19 2008
EXTENSIONS
Name edited by Robert Israel, Jan 07 2015
STATUS
approved