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Numbers n such that the sum of primes dividing n (with repetition) is a Fibonacci number.
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%I #7 Nov 11 2022 13:28:42

%S 1,2,3,5,6,13,15,16,18,22,38,56,63,68,75,80,89,90,93,96,106,108,145,

%T 174,195,208,231,233,234,253,275,289,330,343,352,396,490,494,588,644,

%U 664,695,700,705,747,752,834,836,840,846,884,896,916,920,945,959,1000,1008

%N Numbers n such that the sum of primes dividing n (with repetition) is a Fibonacci number.

%C Conjecture: there are infinitely many consecutive terms in this sequence. For example, sopfr(143335) = 377 and sopfr(143336) = 89 are both Fibonacci numbers.

%H Harvey P. Dale, <a href="/A098833/b098833.txt">Table of n, a(n) for n = 1..1000</a>

%e a(10)=22 because the sum of its prime factors is 13, the 7th

%e Fibonacci number.

%t spdfibQ[n_]:=With[{fibs=Fibonacci[Range[30]]},MemberQ[fibs,Total[ Times@@@ FactorInteger[ n]]]]; Select[Range[1100],spdfibQ] (* _Harvey P. Dale_, Nov 11 2022 *)

%Y Cf. A001414.

%K nonn

%O 1,2

%A _Jason Earls_, Oct 10 2004