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A366386
Excess of n when n is factored into factors q(i) = prime(i)/i: a(n) = A196050(n) - A324923(n).
3
0, 0, 0, 1, 0, 1, 1, 2, 2, 1, 0, 2, 1, 2, 2, 3, 1, 3, 2, 2, 2, 1, 2, 3, 3, 2, 4, 3, 1, 3, 0, 4, 2, 2, 2, 4, 2, 3, 3, 3, 1, 3, 2, 2, 4, 3, 2, 4, 4, 4, 2, 3, 3, 5, 3, 4, 3, 2, 1, 4, 3, 1, 4, 5, 3, 3, 2, 3, 4, 3, 2, 5, 2, 3, 5, 4, 2, 4, 1, 4, 6, 2, 2, 4, 2, 3, 3, 3, 3, 5, 3, 4, 2, 3, 3, 5, 3, 5, 4, 5, 2, 3, 4, 4, 4, 4, 3, 6
OFFSET
1,8
FORMULA
a(n) = A196050(n) - A324923(n).
a(n) <= A358729(n).
PROG
(PARI)
A006530(n) = if(1==n, n, my(f=factor(n)); f[#f~, 1]);
A366386(n) = { my(lista = List([]), gpf, i); while(n > 1, gpf=A006530(n); i = primepi(gpf); n /= gpf; n *= i; listput(lista, i)); #lista - #Set(lista); };
CROSSREFS
Cf. A007097 (positions of 0's), A358731 (of 1's).
Cf. also A046660, A358729.
Sequence in context: A096830 A319780 A141647 * A358729 A001617 A333628
KEYWORD
nonn
AUTHOR
Antti Karttunen, Oct 23 2023
STATUS
approved