Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A074587
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A074587 Sum of the coefficients of the n-th Moebius polynomial, M(n,x), where M(n,-1) = mu(n), the Moebius function of n. +0
9
1, 3, 7, 18, 37, 85, 171, 364, 736, 1513, 3027, 6168, 12337, 24849, 49743, 99872, 199745, 400322, 800645, 1602862, 3205903, 6414837, 12829675, 25665996, 51332030, 102676401, 205353546, 410732134, 821464269, 1642979927, 3285959855 (list; graph; listen)
OFFSET

1,2

COMMENT

It seems that a(n+1)>2*a(n). - Benoit Cloitre (benoit7848c(AT)orange.fr), Aug 26 2002

a(n+1)=2*a(n)+1 if and only if n+1 is prime. - Benoit Cloitre (benoit7848c(AT)orange.fr), Dec 04 2002

LINKS

T. D. Noe, Table of n, a(n) for n=1..300

FORMULA

a(n) = M(n, 1) (see A074586 for definition of M(n, x)). a(n) mod 2 = A008966(n). a(n) is asymptotic to c*2^n with c=1.530191414016549187154362361492633020259512374111... Benoit Cloitre (benoit7848c(AT)orange.fr), Dec 04 2002

a(1)=1 a(n)=1+sum(i=1, n-1, floor(n/i)*a(i)). - Benoit Cloitre (benoit7848c(AT)orange.fr), Dec 04 2002

EXAMPLE

a(5) = M(5,1) = 1+9+15+10+2 = 37, since M(5,x) = 1 + 9x +15x^2 +10x^3 + 2x^4.

MATHEMATICA

m[n_, x_] := m[n, x]=1+x*Sum[m[i, x]Floor[n/i], {i, 1, n-1}]; Table[m[n, 1], {n, 1, 40}]

CROSSREFS

Cf. A074586.

Sequence in context: A069143 A097007 A006124 this_sequence A076700 A026533 A131630

Adjacent sequences: A074584 A074585 A074586 this_sequence A074588 A074589 A074590

KEYWORD

easy,nice,nonn

AUTHOR

Paul D. Hanna (pauldhanna(AT)juno.com), Aug 25 2002

page 1

Search completed in 0.002 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified December 16 17:18 EST 2009. Contains 170825 sequences.


AT&T Labs Research