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A105779 Numbers n such that n + (sum of prime factors of n) = next prime after n. 3
24, 48, 54, 144, 288, 384, 648, 972, 1260, 1728, 1792, 1936, 1944, 2304, 3584, 5184, 6250, 6912, 7168, 8748, 8788, 9216, 9604, 10000, 10125, 10816, 11760, 13122, 13824, 17640, 21632, 21952, 23328, 24255, 25088, 26244, 27648, 33264, 35937, 37752 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Giovanni Resta, Table of n, a(n) for n = 1..10000

EXAMPLE

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

MATHEMATICA

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

PROG

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

is(n)=nextprime(n+1)-n==sopf(n) \\ Charles R Greathouse IV, Jan 10 2014

CROSSREFS

Cf. A050765, A235425.

Sequence in context: A199545 A098427 A105651 * A199105 A074698 A292354

Adjacent sequences:  A105776 A105777 A105778 * A105780 A105781 A105782

KEYWORD

nonn

AUTHOR

Joseph L. Pe, May 06 2005

STATUS

approved

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Last modified June 20 05:01 EDT 2019. Contains 324229 sequences. (Running on oeis4.)