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A324724
a(n) = A001511(A324712(n)), with a(n) = 0 if A324712(n) = 0.
5
0, 1, 1, 1, 1, 3, 1, 3, 1, 1, 1, 1, 1, 3, 2, 5, 1, 1, 1, 3, 1, 2, 1, 4, 1, 2, 3, 1, 1, 3, 1, 4, 2, 2, 2, 3, 1, 3, 3, 6, 1, 4, 1, 1, 1, 2, 1, 4, 1, 1, 8, 1, 1, 3, 1, 3, 3, 4, 1, 2, 1, 2, 3, 4, 2, 1, 1, 1, 2, 2, 1, 3, 1, 2, 1, 1, 2, 1, 1, 4, 5, 2, 1, 1, 4, 2, 3, 4, 1, 1, 1, 1, 2, 2, 3, 5, 1, 4, 1, 2, 1, 1, 1, 8, 3
OFFSET
1,6
FORMULA
If A324712(n) = 0, then a(n) = 0, otherwise a(n) = A001511(A324712(n)).
a(p) = 1 for all primes p.
A324828(n) = [1 == a(n)], where [ ] is the Iverson bracket.
PROG
(PARI)
A324712(n) = { my(v=0); fordiv(n, d, if(issquarefree(n/d), v=bitxor(v,
A323243(d)))); (v); }; \\ Needs also code from A323243.
A001511ext(n) = if(!n, n, sign(n)*(1+valuation(n, 2))); \\ Like A001511 but gives 0 for 0 and -A001511(-n) for negative numbers.
A324724(n) = A001511ext(A324712(n));
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 17 2019
STATUS
approved