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A105779 Numbers n such that n + (sum of prime factors of n) = next prime after n. 3

%I

%S 24,48,54,144,288,384,648,972,1260,1728,1792,1936,1944,2304,3584,5184,

%T 6250,6912,7168,8748,8788,9216,9604,10000,10125,10816,11760,13122,

%U 13824,17640,21632,21952,23328,24255,25088,26244,27648,33264,35937,37752

%N Numbers n such that n + (sum of prime factors of n) = next prime after n.

%H Giovanni Resta, <a href="/A105779/b105779.txt">Table of n, a(n) for n = 1..10000</a>

%e 24 + (sum of prime factors of 24) = 24 + (2 + 3) = 29, the next prime after 24. So 24 belongs to the sequence.

%t Select[Range[2, 10^5], NextPrime[#] == # + Plus @@ First /@ FactorInteger@# &]

%o (PARI) sopf(n)=my(f=factor(n)[,1]); sum(i=1,#f,f[i])

%o is(n)=nextprime(n+1)-n==sopf(n) \\ _Charles R Greathouse IV_, Jan 10 2014

%Y Cf. A050765, A235425.

%K nonn

%O 1,1

%A _Joseph L. Pe_, May 06 2005

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Last modified August 7 19:57 EDT 2020. Contains 336279 sequences. (Running on oeis4.)