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%I #18 Dec 15 2017 17:36:06
%S 2,3,5,7,98,640,735,980,2401,2625,2744,4913,5145,6272,6400,9800,9856,
%T 14336,27440,33614,36015,58564,62720,64000,94325,98000,98560,143360,
%U 188650,232925,252105,274400,298144,336140,401408,405769,465850,570999
%N Numbers whose digital sum is equal to the sum of primes from their smallest to largest prime factor.
%H Donovan Johnson, <a href="/A076406/b076406.txt">Table of n, a(n) for n = 1..500</a>
%e 980 = 2*2*5*7*7 is here since 9+8 = 17 and 2+3+5+7 = 17.
%t okQ[n_]:=Module[{totidn=Total[ IntegerDigits[n]], fctrs,mn,mx}, fctrs= Transpose[FactorInteger[n]][[1]]; mn=Min[fctrs]; mx=Max[fctrs];Total[Prime[Range[PrimePi[mn], PrimePi[mx]]]]==totidn];
%t Select[ Range[2,10000], okQ] (* _Harvey P. Dale_ *)
%K base,nonn
%O 1,1
%A _Jason Earls_, Nov 07 2002
%E a(20)-a(38) from _Donovan Johnson_, Sep 24 2009
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