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A discrete version of the Mangoldt function: if n is prime then round(log(n)) else 0.
5

%I #11 Nov 25 2020 19:33:05

%S 0,1,1,0,2,0,2,0,0,0,2,0,3,0,0,0,3,0,3,0,0,0,3,0,0,0,0,0,3,0,3,0,0,0,

%T 0,0,4,0,0,0,4,0,4,0,0,0,4,0,0,0,0,0,4,0,0,0,0,0,4,0,4,0,0,0,0,0,4,0,

%U 0,0,4,0,4,0,0,0,0,0,4,0,0,0,4,0,0,0,0,0,4,0,0,0,0,0,0,0,5,0,0,0,5,0,5,0,0,0,5,0,5,0,0,0,5,0,0

%N A discrete version of the Mangoldt function: if n is prime then round(log(n)) else 0.

%C The real Mangoldt function Lambda(n) is equal to log(n) if n is prime else 0.

%D T. M. Apostol, Introduction to Analytic Number Theory, Springer-Verlag, 1976, page 32.

%D P. Ribenboim, Algebraic Numbers, p. 44.

%H Antti Karttunen, <a href="/A029833/b029833.txt">Table of n, a(n) for n = 1..65539</a>

%t Table[If[PrimeQ[n],Round[Log[n]],0],{n,200}] (* _Harvey P. Dale_, Nov 25 2020 *)

%o (PARI) A029833(n) = if(!isprime(n),0,round(log(n))); \\ _Antti Karttunen_, Feb 06 2019

%Y Cf. A029832, A029834, A053821.

%K nonn,easy

%O 1,5

%A _N. J. A. Sloane_.

%E More terms from _Antti Karttunen_, Feb 06 2019