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A276440 a(n) = greatest ludic number (A003309) that divides n. 4
1, 2, 3, 2, 5, 3, 7, 2, 3, 5, 11, 3, 13, 7, 5, 2, 17, 3, 1, 5, 7, 11, 23, 3, 25, 13, 3, 7, 29, 5, 1, 2, 11, 17, 7, 3, 37, 2, 13, 5, 41, 7, 43, 11, 5, 23, 47, 3, 7, 25, 17, 13, 53, 3, 11, 7, 3, 29, 1, 5, 61, 2, 7, 2, 13, 11, 67, 17, 23, 7, 71, 3, 1, 37, 25, 2, 77, 13, 1, 5, 3, 41, 83, 7, 17, 43, 29, 11, 89, 5, 91, 23, 3, 47 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

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

Index entries for sequences generated by sieves

EXAMPLE

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.

PROG

(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))))))

CROSSREFS

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

KEYWORD

nonn

AUTHOR

Antti Karttunen, Sep 11 2016

STATUS

approved

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Last modified December 14 05:17 EST 2018. Contains 318090 sequences. (Running on oeis4.)