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A358678
a(n) = 1 if n is odd and sigma(n) == 2 mod 4, otherwise 0.
2
0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 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, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 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, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0
OFFSET
1
FORMULA
a(n) = A000035(n) * A353812(n).
a(n) <= A359150(n).
PROG
(PARI) A358678(n) = ((n%2)&&(2==(sigma(n)%4)));
CROSSREFS
Characteristic function of A191218.
Differs from A359150 for the first time at n=105, where a(105) = 0, while A359150(105) = 1.
Sequence in context: A330551 A346618 A079260 * A359150 A354031 A354035
KEYWORD
nonn
AUTHOR
Antti Karttunen, Dec 17 2022
STATUS
approved