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%I #18 Jan 09 2016 03:04:22
%S 5,63,756,8268,86225,880519,8898517,89471520,897248572,8985712192,
%T 89925825853,899614672173,8997997446679,89989593213308,
%U 899945924502919,8999718992342921,89998539650321017,899992410699128981,8999960560129165187,89999795045731606967
%N Number of n-digit integers x such that x + A007954(x) has n digits, where A007954(x) is the product of decimal digits of x.
%H Hiroaki Yamanouchi, <a href="/A243218/b243218.txt">Table of n, a(n) for n = 1..35</a>
%e For n=1, the five 1-digit integers 0,1,2,3,4 satisfy the condition, with results being respectively 0,2,4,6 and 8, hence a(1)=5.
%o (PARI) DP(n)= my(d = digits(n)); prod(i=1, #d, d[i]);
%o a(n) = {nb = 0; if (n==1, istart = 0, istart = 10^(n-1)); for (i=istart, 10^n-1, if (i + DP(i) < 10^n, nb++);); nb;}
%Y Cf. A007954, A230099, A242945, A243219.
%K nonn,base
%O 1,1
%A _Michel Marcus_, Jun 01 2014
%E a(9)-a(17) from _Hiroaki Yamanouchi_, Sep 29 2014
%E a(18)-a(20) from _Hiroaki Yamanouchi_, Jan 08 2016