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Nonpalindromic numbers k such that k = R(k) + P(k) where R(k) is reversal(k) and P(k) is the product of the digits of k.
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%I #14 Jun 19 2021 12:45:33

%S 354253,385863,398573,534235,653936,676356,682566,695276,853638,

%T 35369253,35639453,45469254,45636454,45839454,53369235,53639435,

%U 54469245,54636445,54839445,55769255,56814665,56941765,59236195

%N Nonpalindromic numbers k such that k = R(k) + P(k) where R(k) is reversal(k) and P(k) is the product of the digits of k.

%C Number of terms below 10^8 is 29.

%C Obviously each palindromic number k that has at least one zero digit also has the property that k = R(k) + P(k), since R(k)=k and P(k)=0.

%C All other terms below 10^8 are 59871495, 65814656, 65941756, 95236159, 95871459 and 99429579.

%C 354253 and 1655425561 are the first two prime terms of the sequence.

%e 354253 = 352453 + 3*5*4*2*5*3 = reversal(354253) + 3*5*4*2*5*3, so 354253 is a term.

%t r[n_] := FromDigits[Reverse[IntegerDigits[n]]]; Do[

%t If[n > r[n] && n == r[n] + Apply[Times, IntegerDigits[n]],

%t Print[n]], {n, 59500000}]

%Y Cf. A004086, A007954, A178271.

%K base,nonn

%O 1,1

%A _Farideh Firoozbakht_, May 23 2010