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!)
A296302 Number of aperiodic compositions of n with relatively prime parts. Number of compositions of n with relatively prime parts and relatively prime run-lengths. 25

%I

%S 1,0,2,5,14,24,62,114,249,480,1022,1978,4094,8064,16348,32520,65534,

%T 130512,262142,523270,1048444,2095104,4194302,8384316,16777185,

%U 33546240,67108356,134201398,268435454,536837136,1073741822,2147418240,4294965244,8589803520

%N Number of aperiodic compositions of n with relatively prime parts. Number of compositions of n with relatively prime parts and relatively prime run-lengths.

%H Robert G. Wilson v, <a href="/A296302/b296302.txt">Table of n, a(n) for n = 1..1000</a>

%F a = mu * mu * c, where * is Dirichlet convolution and c(n) = 2^(n-1).

%e The a(6) = 24 aperiodic compositions with relatively prime parts are:

%e (15), (51),

%e (114), (123), (132), (141), (213), (231), (312), (321), (411),

%e (1113), (1122), (1131), (1221), (1311), (2112), (2211), (3111),

%e (11112), (11121), (11211), (12111), (21111).

%t Table[DivisorSum[n,Function[d,MoebiusMu[n/d]*DivisorSum[d,MoebiusMu[#]*2^(d/#-1)&]]],{n,20}]

%Y Cf. A000005, A000740, A000837, A007427, A008683, A008965, A059966, A060223, A100953, A228369, A281013.

%K nonn

%O 1,3

%A _Gus Wiseman_, Dec 11 2017

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 August 11 00:32 EDT 2020. Contains 336403 sequences. (Running on oeis4.)