A356161 - OEIS

%I #9 Jul 28 2022 15:17:54

%S 1,0,0,1,1,0,1,1,0,0,1,0,1,0,0,1,1,0,1,0,0,0,1,0,0,0,0,1,1,0,1,1,0,0,

%T 0,0,1,0,0,0,1,0,1,1,0,0,1,0,0,0,0,1,1,0,0,0,0,0,1,0,1,0,0,1,0,0,1,1,

%U 0,0,1,0,1,0,0,1,0,0,1,0,0,0,1,0,0,0,0,1,1,0,0,1,0,0,0,0,1,0,0,0,1,0,1,1,0,0,1,1,1,0,0,0,1,0,0,1,0,0,0,0,1

%N a(n) = 1 if the smallest positive k such that n divides k*A276086(k) is equal to n, otherwise 0, where A276086 is primorial base exp-function.

%H Antti Karttunen, <a href="/A356161/b356161.txt">Table of n, a(n) for n = 1..65537</a>

%H <a href="/index/Ch#char_fns">Index entries for characteristic functions</a>

%H <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a>

%F a(n) = [A355944(n) == n] = [A355945(n) == 0], where [ ] is the Iverson bracket.

%o (PARI)

%o A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };

%o A356161(n) = for(k=1, oo, if((k*A276086(k))%n==0, return(n==k)));

%Y Characteristic function of A356160.

%Y Cf. A276086, A324580, A355944, A355945.

%K nonn

%O 1

%A _Antti Karttunen_, Jul 28 2022