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A324539 Number of divisors d of n such that A276086(d) = (n/d). 5
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, 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, 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 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2250
COMMENTS
a(n) tells how many times n occurs in A324580. See also comments in A324541.
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 ?
LINKS
FORMULA
a(n) = Sum_{d|n} [d == A276086(n/d)], where [ ] is the Iverson bracket.
PROG
(PARI)
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; };
A324539(n) = sumdiv(n, d, (d==A276086(n/d)));
CROSSREFS
Cf. A276086, A324540 (positions of zeros), A324541 (nonzeros), A324580.
Sequence in context: A153638 A122415 A241666 * A324964 A285957 A292273
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 10 2019
STATUS
approved

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Last modified July 18 09:18 EDT 2024. Contains 374378 sequences. (Running on oeis4.)