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1,2

Antti Karttunen, Table of n, a(n) for n = 1..10001

Index entries for sequences generated by sieves

a(19) = 1 as 19 is not a ludic number, but it is a prime, thus only ludic number that divides it is the very first one A003309(1) = 1.

a(589) = 1 also as 589 = 19*31 and both 19 and 31 are in A192505.

(Scheme)

(define (A276440 n) (let loop ((k 1) (mt 1)) (let ((t (A003309 k))) (cond ((> t n) mt) ((zero? (modulo n t)) (loop (+ 1 k) t)) (else (loop (+ 1 k) mt))))))

Cf. A003309, A192505, A272565, A276568, A276569.

Differs from A006530 for the first time at n=19.

Sequence in context: A197861 A180506 A273283 * A162325 A197862 A006530

Adjacent sequences: A276437 A276438 A276439 * A276441 A276442 A276443

nonn

Antti Karttunen, Sep 11 2016

approved