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Numbers n such that n=(d_1+2)*(d_2+2)*...*(d_k+2) where d_1 d_2 ... d_k is the decimal expansion of n.
5

%I #8 Jan 26 2015 00:38:13

%S 12,24,35,56

%N Numbers n such that n=(d_1+2)*(d_2+2)*...*(d_k+2) where d_1 d_2 ... d_k is the decimal expansion of n.

%C It seems that there are no further terms.

%C No other terms below 10^150. - _Max Alekseyev_, Jan 25 2015

%e 56 is in the sequence because 56=(5+2)*(6+2).

%t Do[d=IntegerDigits[n];k=Length[d];If[n==Product[d[[j]]+2, {j, k}], Print[n]], {n, 10000000}]

%Y Cf. A098114, A097371, A097372.

%K base,nonn,more,hard

%O 1,1

%A _Farideh Firoozbakht_, Sep 24 2004