The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A349358 Dirichlet inverse of A064216, which is A064989(2n-1), where A064989 is fully multiplicative with a(2) = 1 and a(p) = prevprime(p) for odd primes p. 3

%I #8 Nov 25 2021 20:34:36

%S 1,-2,-3,-1,-4,5,-11,6,-4,-1,-10,3,-9,36,1,-24,-14,25,-31,38,29,-1,

%T -12,-29,-9,10,4,-11,-34,53,-59,62,27,-5,50,-41,-71,106,19,-83,-16,

%U -125,-39,98,51,-7,-58,184,32,112,-13,-15,-30,-84,-27,-170,77,79,-44,-109,-49,162,184,-84,-10,31,-85,192,-59,-75,-86

%N Dirichlet inverse of A064216, which is A064989(2n-1), where A064989 is fully multiplicative with a(2) = 1 and a(p) = prevprime(p) for odd primes p.

%H Antti Karttunen, <a href="/A349358/b349358.txt">Table of n, a(n) for n = 1..16384</a>

%H <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>

%F a(1) = 1; a(n) = -Sum_{d|n, d < n} A064216(n/d) * a(d).

%F a(n) = A349359(n) - A064216(n).

%o (PARI)

%o A064989(n) = { my(f = factor(n)); if((n>1 && f[1,1]==2), f[1,2] = 0); for (i=1, #f~, f[i,1] = precprime(f[i,1]-1)); factorback(f); };

%o A064216(n) = A064989((2*n)-1);

%o memoA349358 = Map();

%o A349358(n) = if(1==n,1,my(v); if(mapisdefined(memoA349358,n,&v), v, v = -sumdiv(n,d,if(d<n,A064216(n/d)*A349358(d),0)); mapput(memoA349358,n,v); (v)));

%Y Cf. A064216, A064989, A349359, A349398.

%Y Cf. also A323893, A349125.

%K sign

%O 1,2

%A _Antti Karttunen_, Nov 17 2021

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 23 14:23 EDT 2024. Contains 372763 sequences. (Running on oeis4.)