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A324539 Number of divisors d of n such that A276086(d) = (n/d).

%I A324539 #10 Mar 10 2019 19:31:28
%S A324539 0,1,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,
%T A324539 0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
%U A324539 0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1
%N A324539 Number of divisors d of n such that A276086(d) = (n/d).
%C A324539 a(n) tells how many times n occurs in A324580. See also comments in A324541.
%C A324539 Question: Where is the next term larger than one in this sequence after a(2250) = 2 and a(5402250) = 2 ? Are there terms larger than 2 ?
%H A324539 Antti Karttunen, <a href="/A324539/b324539.txt">Table of n, a(n) for n = 1..100000</a>
%H A324539 <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a>
%H A324539 <a href="/index/Pri#primorial_numbers">Index entries for sequences related to primorial numbers</a>
%F A324539 a(n) = Sum_{d|n} [d == A276086(n/d)], where [ ] is the Iverson bracket.
%o A324539 (PARI)
%o A324539 A276086(n) = { my(i=0,m=1,pr=1,nextpr); while((n>0),i=i+1; nextpr = prime(i)*pr; if((n%nextpr),m*=(prime(i)^((n%nextpr)/pr));n-=(n%nextpr));pr=nextpr); m; };
%o A324539 A324539(n) = sumdiv(n,d,(d==A276086(n/d)));
%Y A324539 Cf. A276086, A324540 (positions of zeros), A324541 (nonzeros), A324580.
%K A324539 nonn
%O A324539 1,2250
%A A324539 _Antti Karttunen_, Mar 10 2019