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A378539
Characteristic function for numbers that have Zumkeller divisors.
2
0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1
OFFSET
1
COMMENTS
Differs from A294936 at n=748, 7544, 10184, 56816, 61904, 62416, 66928, 69488, 73616, 102416, ..., that might be a subsequence of A378538.
FORMULA
a(n) = [A378446(n) > 0], where [ ] is the Iverson bracket.
a(n) >= A378537(n).
PROG
(PARI)
A378446(n) = sumdiv(n, d, A083206(d));
A378539(n) = (A378446(n)>0);
CROSSREFS
Characteristic function of A376880.
Different from A294936.
Sequence in context: A133944 A210455 A294936 * A296210 A368990 A094912
KEYWORD
nonn
AUTHOR
Antti Karttunen, Dec 02 2024
STATUS
approved