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%I #3 Dec 05 2013 19:56:53
%S 1,2,3,4,5,6,7,8,9,25,32,36,64,125,128,135,175,216,243,250,256,324,
%T 375,384,432,512,625,672,729,735,784,864,875,1024,1250,1296,1372,1715,
%U 1764,1792,2048,2304,2500,2560,2592,2744,2916,3072,3087,3125,3375,3456,3645
%N Numbers which can be obtained as the product of one or more of their digits (used with multiplicity).
%C Subsequence of the 7-smooth numbers (A002473).
%C For 2 <= d <=9, powers of d that contain digit d are in the sequence, e.g. every power of 5 and every odd power of 9.
%e 64 is a member as 64 = 4*4*4; 135 is a member as 135 = 3*3*3*5.
%o (PARI) digits29(n) = local(v,d);v=[];while(n>0,d=divrem(n,10);n=d[1];if(d[2]>1,v=concat(d[2],v)));v {recdiv(n,s) = local(b,j,d);b=0;j=1;while(b<1&&j<=length(s),d=divrem(n,s[j]);if(d[2]==0,if(d[1]>1,b=recdiv(d[1],s),b=1));j++);b} for(n=1,3650,if(n==1||recdiv(n,digits29(n)),print1(n,",")))
%Y Cf. A002473.
%K base,easy,nonn
%O 1,2
%A _Amarnath Murthy_, Nov 22 2004
%E Edited, corrected and extended by _Klaus Brockhaus_, Nov 25 2004