A378537 Characteristic function for primitive Zumkeller numbers.

0, 0, 0, 0, 0, 1, 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, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 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, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0

Offset

1

Comments

Differs from A341619 at n = 748, 7544, 8228, 10184, ..., A378538.

Links

Antti Karttunen, Table of n, a(n) for n = 1..108045

Index entries for characteristic functions

Formula

a(n) = [A083206(n) > 0 and A083206(n) = A378446(n)], where [ ] is the Iverson bracket.

a(n) <= A179527(n).

a(n) <= A378539(n).

Prog

(PARI)
A378446(n) = sumdiv(n, d, A083206(d));
A378537(n) = (A083206(n) && (A083206(n)==A378446(n)));
(PARI) A378537(n) = if(!A179527(n), 0, fordiv(n, d, if(d<n && A179527(d), return(0))); (1));

Crossrefs

Characteristic function of A180332.

Cf. A083206, A179527, A341619, A378446, A378538, A378539.

Cf. also A378454.

Sequence in context: A378529 A378448 A341619 * A302049 A373383 A078926

Adjacent sequences: A378534 A378535 A378536 * A378538 A378539 A378540

Keyword

nonn,new

Author

Antti Karttunen, Dec 02 2024

Status

approved