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A324828
a(n) = A324543(n) read modulo 2, where A324543 is the Möbius-transform of sigma(A156552(n)).
5
0, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 1, 1, 1, 0, 0, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 1, 0, 1, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 0, 0, 0
OFFSET
1
FORMULA
a(n) = A324543(n) mod 2 = A324712(n) mod 2 = A324715(n) mod 2.
a(p) = 1 for all primes p.
PROG
(PARI)
A324543(n) = sumdiv(n, d, moebius(n/d)*A323243(d)); \\ Needs also code from A323243.
A324828(n) = (A324543(n)%2);
(PARI)
A324712(n) = { my(v=0); fordiv(n, d, if(issquarefree(n/d), v=bitxor(v, A323243(d)))); (v); };
A324828(n) = (A324712(n)%2);
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 16 2019
STATUS
approved