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%I #13 Jul 16 2018 19:27:40
%S 1,11,12,36,111,112,128,144,212,216,224,333,432,448,612,1111,1112,
%T 1116,1212,1296,1332,1424,2112,2144,2212,2224,2232,2916,3132,3312,
%U 3636,4112,4144,4224,4288,4464,6336,6624,8128,8448,9396,11111,11112,11133,11172,11212
%N Numbers divisible by the square of each digit.
%C Includes all repunits.
%H Christian N. K. Anderson, <a href="/A225299/b225299.txt">Table of n, a(n) for n = 1..5000</a>
%e a(7) 128 is divisible by 1^2, by 2^2, and by 8^2.
%t d[n_]:=IntegerDigits[n]; t={}; Do[If[!MemberQ[d[n],0] && Union[Mod[n,d[n]^2]] == {0}, AppendTo[t,n]], {n,11220}]; t (* _Jayanta Basu_, May 15 2013 *)
%t Select[Range[12000],DigitCount[#,10,0]==0&&And@@Divisible[ #,IntegerDigits[ #]^2]&] (* _Harvey P. Dale_, Jul 16 2018 *)
%o (R) isint<-function(x) x==as.integer(x)
%o sqalldig<-function(x) as.numeric(strsplit(as.character(x),"")[[1]])^2
%o divby<-function(x) ifelse(length(grep(0,x))>0,F,all(isint(x/sqalldig(x))))
%o which(sapply(1:1000,divby))
%Y Cf. A132359, A034709, A034837, A005349, A007602, A034838.
%K nonn,base
%O 1,2
%A _Kevin L. Schwartz_ and _Christian N. K. Anderson_, May 04 2013