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A105651 Numbers n such that n + smallest prime factor of n + largest prime factor of n = next prime after n. 1
24, 48, 54, 90, 120, 140, 144, 288, 300, 360, 384, 450, 480, 528, 648, 720, 900, 960, 972, 1080, 1386, 1400, 1440, 1584, 1672, 1728, 1792, 1848, 1936, 1944, 2304, 2430, 2450, 2700, 2880, 3230, 3584, 3600, 3840, 4180, 4320, 4500, 5184, 5400, 5544, 5940 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

EXAMPLE

24 + smallest prime factor of 24 + largest prime factor of 24 = 24 + 2 + 3 = 29 = next prime after 24. So 24 belongs to the sequence.

MATHEMATICA

<< NumberTheory`NumberTheoryFunctions` Select[Range[2, 10^4], # + Last[Transpose[FactorInteger[ # ]][[1]]] + First[Transpose[FactorInteger[ # ]][[1]]] == NextPrime[ # ] &]

CROSSREFS

Sequence in context: A040552 A199545 A098427 * A105779 A199105 A329884

Adjacent sequences:  A105648 A105649 A105650 * A105652 A105653 A105654

KEYWORD

nonn

AUTHOR

Joseph L. Pe, May 04 2005

STATUS

approved

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Last modified March 30 22:55 EDT 2020. Contains 333132 sequences. (Running on oeis4.)