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A323158
If n is a square, a(n) = 1-(n mod 2), otherwise a(n) = (n mod 2); a(n) = A049820(n) mod 2, where A049820(n) = n - number of divisors of n.
1
0, 0, 1, 1, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0
OFFSET
1
COMMENTS
For all i, j: A305801(i) = A305801(j) => a(i) = a(j).
FORMULA
a(n) = A000035(A049820(n)) = A000035(n+A010052(n)).
PROG
(PARI) A323158(n) = ((n-numdiv(n))%2);
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jan 09 2019
STATUS
approved