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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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1 LINKS Antti Karttunen, Table of n, a(n) for n = 1..100000 Index entries for characteristic functions 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. Cf. A000035, A000203, A353812. 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 Adjacent sequences: A358675 A358676 A358677 * A358679 A358680 A358681 KEYWORD nonn AUTHOR Antti Karttunen, Dec 17 2022 STATUS approved

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Last modified September 14 06:54 EDT 2024. Contains 375920 sequences. (Running on oeis4.)