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Numbers k such that the divisors of k are divisible by all digits of their divisors.
1

%I #30 Dec 20 2021 02:41:16

%S 1,2,3,4,5,6,7,8,9,11,12,15,22,24,33,44,55,66,77,88,99,132,264,

%T 1111111111111111111,2222222222222222222,3333333333333333333,

%U 4444444444444444444,5555555555555555555,6666666666666666666,7777777777777777777,8888888888888888888

%N Numbers k such that the divisors of k are divisible by all digits of their divisors.

%C Subsequence of A209933 (numbers that are divisible by all digits of their divisors).

%C All divisors of numbers in this sequence are also in the sequence.

%C The primitive elements of this sequence are A116692. No member of this sequence is divisible by a prime outside this sequence. - _Charles R Greathouse IV_, Apr 17 2012

%e Number 48 with divisors 1, 2, 3, 4, 6, 8, 12, 16, 24, 48 is not in the sequence because 6 is not a divisor of 16.

%o (PARI) all(n)=my(v=vecsort(eval(Vec(Str(n))),,8)); if(v[1]==0, return(0)); for(i=1,#v,if(n%v[i],return(0)));1

%o is(n)=fordiv(n,d,if(!all(d),return(0)));1 \\ _Charles R Greathouse IV_, Apr 17 2012

%o (Haskell)

%o import Data.List ((\\))

%o a182183 n = a182183_list !! (n-1)

%o a182183_list = f a209933_list [1] where

%o f (x:xs) ys =

%o if null (a027751_row x \\ ys) then x : f xs (x : ys) else f xs ys

%o -- _Reinhard Zumkeller_, Apr 19 2012

%Y Subsequence of A034838. A116692 is a subsequence.

%Y Cf. A209933.

%Y Cf. A027751.

%Y Cf. A027751.

%K nonn,base

%O 1,2

%A _Jaroslav Krizek_, Apr 17 2012

%E a(24)-a(31) from _Charles R Greathouse IV_, Apr 17 2012

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Last modified September 23 16:16 EDT 2024. Contains 376178 sequences. (Running on oeis4.)