A360073 - OEIS

%I #11 Jan 27 2023 03:13:55

%S 1,2,3,4,5,6,7,8,9,5,11,12,1,7,15,8,1,9,1,5,7,11,1,24,5,2,9,7,1,15,1,

%T 8,11,2,7,36,1,2,3,8,1,7,1,11,15,2,1,24,7,5,3,4,1,9,11,8,3,2,1,15,1,2,

%U 9,8,5,11,1,4,3,7,1,36,1,2,15,4,11,6,1,8,9

%N a(n) is the greatest divisor of n divisible by the product of its own digits.

%C Numbers divisible by the product of their digits are called Zuckerman numbers (A007602).

%H Rémy Sigrist, <a href="/A360073/b360073.txt">Table of n, a(n) for n = 1..10000</a>

%H <a href="/index/Di#divisors">Index entries for sequences related to divisors</a>

%F a(n) = n iff n belongs to A007602.

%e For n = 10:

%e - the divisors of 10 are 1, 2, 5 and 10,

%e - 5 is divisible by 5 whereas 10 is not divisible by 1*0,

%e - so a(10) = 5.

%o (PARI) a(n) = { fordiv (n, d, my (t=n/d, p=vecprod(digits(t))); if (p && t%p==0, return (t))) }

%Y Cf. A007602, A335037, A337941, A360074.

%K nonn,base,easy

%O 1,2

%A _Rémy Sigrist_, Jan 24 2023