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%I #22 Mar 15 2015 14:56:58
%S 1,2,3,4,5,6,7,8,9,24,37,45,48,67,71,79,100,228,231,256,259,292,388,
%T 400,524,575,624,661,832,865,868,900,928,949,973,985,1024,1089,1231,
%U 1317,1344,1399,1541,1549,1564,1600,1612,1629,1723,1759,2025,2164,2209
%N Positive numbers which when decremented by the product of their digits produce a square.
%H Alois P. Heinz, <a href="/A228187/b228187.txt">Table of n, a(n) for n = 1..1000</a>
%e 388 is a term because 388-(3*8*8) = 196 = 14^2.
%p a:= proc(n) option remember; local d, k, m;
%p for k from 1+`if`(n=1, 0, a(n-1)) do
%p d, m:= 1, k;
%p while m>0 do d:=d*irem(m,10,'m') od;
%p if issqr(k-d) then return k fi
%p od
%p end:
%p seq(a(n), n=1..100); # _Alois P. Heinz_, Aug 19 2013
%o (PARI) for(n=0,10^4,d=digits(n);p=prod(i=1,#d,d[i]);if(issquare(n-p),print(n,", "))) \\ _Derek Orr_, Mar 13 2015
%Y Cf. A066567.
%K base,nonn,easy
%O 1,2
%A _Derek Orr_, Aug 15 2013
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