login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A077598 Coefficient of x^2 in the n-th Moebius polynomial (A074586), M(n,x), which satisfies M(n,-1)=mu(n) the Moebius function of n. 6
0, 0, 2, 8, 15, 30, 43, 67, 90, 123, 149, 203, 237, 290, 343, 415, 464, 556, 613, 716, 800, 899, 972, 1126, 1218, 1342, 1458, 1616, 1716, 1916, 2026, 2215, 2365, 2540, 2690, 2959, 3098, 3300, 3485, 3762, 3919, 4221, 4388, 4667, 4921, 5179, 5364, 5762 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

These terms seem to be asymptotic to c*n^2*log(n) with c=0.69...

LINKS

Table of n, a(n) for n=1..48.

EXAMPLE

These are the coefficients of x^2 in the Moebius polynomials, which begin: M(1,x)=1; M(2,x)=1 + 2x; M(3,x)=1 + 4x + 2x^2; M(4,x)=1 + 7x + 8x^2 + 2x^3; M(5,x)=1 + 9x +15x^2 +10x^3 + 2x^4; M(6,x)=1 +13x +30x^2 +27x^3 +12x^4 + 2x^5; M(7,x)=1 +15x +43x^2 +57x^3 +39x^4 +14x^5 + 2x^6; M(8,x)=1 +19x +67x^2+108x^3 +98x^4 +53x^5 +16x^6 + 2x^7.

MATHEMATICA

m[n_, 1] = 1; m[n_, k_] := m[n, k] = Sum[Floor[n/j]*m[j, k - 1], {j, 1, n - 1}]; a[n_] := m[n, 3]; Table[a[n], {n, 1, 48}] (* Jean-Fran├žois Alcover, Jun 18 2013 *)

CROSSREFS

Cf. A074586, A074587, A077596, A077597, A077599, A077600, A077601.

Sequence in context: A244476 A292202 A189952 * A095298 A297734 A100596

Adjacent sequences:  A077595 A077596 A077597 * A077599 A077600 A077601

KEYWORD

nonn

AUTHOR

Benoit Cloitre and Paul D. Hanna, Nov 10 2002

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified July 23 11:34 EDT 2021. Contains 346259 sequences. (Running on oeis4.)