cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A288069 Quotients obtained when the Zuckerman numbers are divided by the product of their digits.

This page as a plain text file.
%I A288069 #43 Apr 12 2025 11:56:12
%S A288069 1,1,1,1,1,1,1,1,1,11,6,3,3,2,111,56,23,8,22,9,9,5,53,18,14,52,21,4,
%T A288069 18,51,13,8,7,17,1111,556,371,223,186,377,28,37,19,303,12,437,74,28,
%U A288069 59,9,49,528,67,93,27,1037,174,22,151,13,184,29,514,66,46
%N A288069 Quotients obtained when the Zuckerman numbers are divided by the product of their digits.
%C A288069 The Zuckerman numbers (A007602) are the numbers that are divisible by the product of their digits.
%C A288069 Question: Is A067251 a subsequence? No, it appears in A056770 that not all integers other than multiples of 10 can be obtained as quotient, such as 15, 16, 24, 25, 26, 32, .... (see A342941).
%C A288069 The limit of the sequence is infinite: for any x, there is some N such that, for all n > N, a(n) > x. Proof: a Zuckerman number with d digits is at least 10^(d-1) and has a digit product at most 9^d and so has a quotient at least 10^(d-1)/9^d which goes to infinity with d. - _Charles R Greathouse IV_, Jun 05 2017
%C A288069 The repunits A002275 are a subsequence. - _Peter Schorn_, Apr 05 2025
%H A288069 Charles R Greathouse IV, <a href="/A288069/b288069.txt">Table of n, a(n) for n = 1..10000</a>
%e A288069 a(11) = 12/(1*2) = 6; a(13) = 24/(2*4) = 3.
%p A288069 f:= proc(n) local L,p;
%p A288069    p:= convert(convert(n,base,10),`*`);
%p A288069    if p > 0 then
%p A288069      if n mod p = 0 then return n/p fi
%p A288069    fi
%p A288069 end proc:
%p A288069 map(f, [$1..10^4]); # _Robert Israel_, Jun 05 2017
%t A288069 Select[Table[n/Max[Times@@IntegerDigits[n],Pi/100],{n,5000}],IntegerQ] (* _Harvey P. Dale_, Aug 16 2021 *)
%Y A288069 Cf. A007602, A067251, A056770, A342593, A342941, A002275.
%K A288069 nonn,base
%O A288069 1,10
%A A288069 _Bernard Schott_, Jun 05 2017