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A075654 Numbers n such that n + sum of prime factors of n = (n+1) + sum of prime factors of (n+1). 1
3, 14, 152, 224, 285, 455, 902, 1518, 2013, 2079, 4823, 6655, 7104, 7584, 8493, 8532, 9416, 14344, 15687, 18569, 20115, 20163, 20490, 22351, 25543, 26123, 28250, 28564, 30744, 37305, 37406, 41261, 45844, 50609, 51992, 54137, 56563, 60651 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

EXAMPLE

14 + sum of prime factors of 14 = 14 + 2 + 7 = 23; 15 + sum of prime factors of 15 = 15 + 3 + 5 = 23; hence 14 belongs to the sequence.

MATHEMATICA

s[n_] := n + Apply[Plus, Transpose[FactorInteger[n]][[1]]]; Select[Range[2, 10^5], s[ # ] == s[ # + 1] &]

SequencePosition[Table[n+Total[FactorInteger[n][[All, 1]]], {n, 70000}], {x_, x_}][[All, 1]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jun 23 2017 *)

CROSSREFS

Cf. A008472, A075653.

Sequence in context: A073550 A319361 A002966 * A330603 A261006 A185238

Adjacent sequences:  A075651 A075652 A075653 * A075655 A075656 A075657

KEYWORD

nonn

AUTHOR

Joseph L. Pe, Oct 11 2002

STATUS

approved

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Last modified June 15 08:52 EDT 2021. Contains 345048 sequences. (Running on oeis4.)