

A114946


Number of monic irreducible polynomials over GF(4) of degree <= n.


2



4, 10, 30, 90, 294, 964, 3304, 11464, 40584, 145338, 526638, 1924378, 7086598, 26259388, 97842104, 366273464, 1376854004, 5194587924, 19661846184, 74637375132, 284068160592, 1083712790142, 4143223406562, 15871346734402, 60907343008066, 234122710710436
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OFFSET

1,1


LINKS

Table of n, a(n) for n=1..26.


MAPLE

with(numtheory):
b:= n> add(mobius(d) *4^(n/d)/n, d=divisors(n)):
a:= n> add(b(k), k=1..n):
seq(a(n), n=1..30); # Alois P. Heinz, Sep 23 2008


PROG

(PARI) a(n)=sum(m=1, n, 1/m* sumdiv(m, d, moebius(d)*4^(m/d) ) ); /* Joerg Arndt, Jul 04 2011 */


CROSSREFS

Partial sums of A027377. 4th column of A143328.  Alois P. Heinz, Sep 23 2008
Sequence in context: A036674 A006357 A047088 * A243793 A001551 A067142
Adjacent sequences: A114943 A114944 A114945 * A114947 A114948 A114949


KEYWORD

nonn


AUTHOR

Gary L Mullen (mullen(AT)math.psu.edu) and Ken Hicks, Jan 06 2006


EXTENSIONS

More terms from Alois P. Heinz, Sep 23 2008


STATUS

approved



