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%I #27 Jan 16 2015 19:23:34
%S 0,19,29,39,49,59,69,79,89,99
%N Numbers n such that n = (product of digits of n) + (sum of digits of n).
%C A number n with m digits belongs to the sequence if K1*K2*K3*...*Km-9_(m-1)*K1-9_(m-2)*K2....=0 where Ki are the digits of n and 9_(m-1) is a repdigit with 9 repeated (m-1) times. Hence m=2, so sequence is complete.
%p select(proc(t) local d; d:= convert(t,base,10); convert(d,`+`)+convert(d,`*`)=t end proc, [$0..100]); # _Robert Israel_, Dec 16 2014
%t Select[Range[100], # == Times @@ IntegerDigits[#] + Plus @@ IntegerDigits[#] &] (* _Michael De Vlieger_, Dec 26 2014 *)
%o (PARI) isok(n) = my(d=digits(n)); n == (sum(i=1, #d, d[i]) + prod(i=1, #d, d[i])); \\ _Michel Marcus_, Apr 06 2014
%K fini,nonn,base,full
%O 1,2
%A _Felice Russo_
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