This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A114946 #20 Aug 24 2023 02:31:32 %S A114946 4,10,30,90,294,964,3304,11464,40584,145338,526638,1924378,7086598, %T A114946 26259388,97842104,366273464,1376854004,5194587924,19661846184, %U A114946 74637375132,284068160592,1083712790142,4143223406562,15871346734402,60907343008066,234122710710436 %N A114946 Number of monic irreducible polynomials over GF(4) of degree <= n. %p A114946 with(numtheory): %p A114946 b:= n-> add(mobius(d) *4^(n/d)/n, d=divisors(n)): %p A114946 a:= n-> add(b(k), k=1..n): %p A114946 seq(a(n), n=1..30); # _Alois P. Heinz_, Sep 23 2008 %t A114946 f[n_] := DivisorSum[n, MoebiusMu[#] * 4^(n/#) &] / n; Accumulate[Array[f, 26]] (* _Amiram Eldar_, Aug 24 2023 *) %o A114946 (PARI) a(n)=sum(m=1, n, 1/m* sumdiv(m, d, moebius(d)*4^(m/d) ) ); /* _Joerg Arndt_, Jul 04 2011 */ %Y A114946 Partial sums of A027377. 4th column of A143328. - _Alois P. Heinz_, Sep 23 2008 %K A114946 nonn %O A114946 1,1 %A A114946 Gary L Mullen (mullen(AT)math.psu.edu) and Ken Hicks, Jan 06 2006 %E A114946 More terms from _Alois P. Heinz_, Sep 23 2008