This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A029832 #13 Jul 08 2025 19:22:26
%S A029832 0,1,2,0,2,0,2,0,0,0,3,0,3,0,0,0,3,0,3,0,0,0,4,0,0,0,0,0,4,0,4,0,0,0,
%T A029832 0,0,4,0,0,0,4,0,4,0,0,0,4,0,0,0,0,0,4,0,0,0,0,0,5,0,5,0,0,0,0,0,5,0,
%U A029832 0,0,5,0,5,0,0,0,0,0,5,0,0,0,5,0,0,0,0,0,5,0,0,0,0,0,0,0,5,0,0,0,5,0,5,0,0,0,5,0,5,0,0,0,5,0,0
%N A029832 A discrete version of the Mangoldt function: if n is prime then ceiling(log(n)) else 0.
%C A029832 The real Mangoldt function Lambda(n) is equal to log(n) if n is prime else 0.
%D A029832 T. M. Apostol, Introduction to Analytic Number Theory, Springer-Verlag, 1976, page 32.
%D A029832 P. Ribenboim, Algebraic Numbers, p. 44.
%H A029832 Antti Karttunen, <a href="/A029832/b029832.txt">Table of n, a(n) for n = 1..65539</a>
%t A029832 Table[If[PrimeQ[n],Ceiling[Log[n]],0],{n,120}] (* _Harvey P. Dale_, Aug 23 2019 *)
%o A029832 (PARI) A029832(n) = if(!isprime(n),0,ceil(log(n))); \\ _Antti Karttunen_, Feb 06 2019
%Y A029832 Cf. A029833, A029834, A053821.
%K A029832 nonn,easy
%O A029832 1,3
%A A029832 _N. J. A. Sloane_
%E A029832 More terms from _Antti Karttunen_, Feb 06 2019