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 A140175 Numbers n such that n=prime((d_1*d_2*...*d_k)*(d_1+d_2+...+d_k)) where d_1d_2...d_k is the decimal expansion of n. 1
 4621, 34361, 2881861, 63882851 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Table of n, a(n) for n=1..4. EXAMPLE 63882851=prime((6*3*8*8*2*8*5*1)*(6+3+8+8+2+8+5+1)). MATHEMATICA fQ[n_] := Block[{id = IntegerDigits@ n}, n == Prime[Plus @@ id Times @@ id]]; k = 1; lst = {}; While[ k < 10^8, If[ fQ@n, AppendTo[lst, k]; Print@ n]; k++ ]; lst (* Robert G. Wilson v *) CROSSREFS Cf. A097223. Sequence in context: A338337 A237634 A051649 * A116226 A115446 A358445 Adjacent sequences: A140172 A140173 A140174 * A140176 A140177 A140178 KEYWORD base,nonn AUTHOR Farideh Firoozbakht, Jun 09 2008 STATUS approved

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Last modified September 10 03:08 EDT 2024. Contains 375770 sequences. (Running on oeis4.)