A286590 - OEIS

%I #21 Feb 16 2021 04:33:26

%S 1,3,9,21,33,45,81,153,165,201,393,405,441,645,873,885,921,1113,1125,

%T 1161,1365,2313,2565,3765,4005,5913,5925,5961,6153,6165,6201,6405,

%U 7353,7641,8805,9045,15993,16281,17433,26085,26325,36393,36645,46233,46245,46281,46473,46485,46521,46725,47673

%N Numbers that are divisible by the product of their factorial base digits (A208575).

%C After the initial 1, all terms are multiples of three.

%H Amiram Eldar, <a href="/A286590/b286590.txt">Table of n, a(n) for n = 1..500</a> (terms 1..120 from Antti Karttunen)

%H <a href="/index/Fa#facbase">Index entries for sequences related to factorial base representation</a>

%t max = 8; Select[Range[max!], FreeQ[(d = IntegerDigits[#, MixedRadix[Range[max, 2, -1]]]), 0] && Divisible[#, Times @@ d] &] (* _Amiram Eldar_, Feb 16 2021 *)

%o (Scheme, with _Antti Karttunen_'s IntSeq-library)

%o (define A286590 (MATCHING-POS 1 1 (lambda (n) (let ((k (A208575 n))) (and (not (zero? k)) (zero? (modulo n k)))))))

%Y Cf. A007489 (a subsequence), A208575, A118363.

%Y Cf. A007602 (for base-10 analog).

%K nonn,base

%O 1,2

%A _Antti Karttunen_, Jun 18 2017