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A073938 Numbers n such that A078142(n) = A078142(n+1) = A078142(n+2), where A078142(n) is the sum of the differences of the distinct prime factors p of n and the next square larger than p. 1
153, 3009, 3288, 5170, 5364, 11186, 11295, 11395, 12874, 13545, 16288, 17892, 27760, 28118, 34187, 38907, 47650, 55282, 63455, 64972, 65290, 95886, 104718, 106793, 110944, 155573, 163964, 169644, 172081, 187164, 202607, 203255, 204609 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Are there infinitely many k-tuples in A078142?

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..5000

MATHEMATICA

s[n_] := Total[Ceiling[Sqrt[(p = FactorInteger[n][[;; , 1]])]]^2 - p]; s1 = s2 = 0; seq = {}; Do[s3 = s[n]; If[s1 == s2 == s3, AppendTo[seq, n - 2]]; s1 = s2; s2 = s3, {n, 3, 2*10^5}]; seq (* Amiram Eldar, Dec 08 2019 *)

CROSSREFS

Cf. A071247, A078142.

Sequence in context: A014576 A087414 A184369 * A278285 A111086 A269664

Adjacent sequences: A073935 A073936 A073937 * A073939 A073940 A073941

KEYWORD

nonn

AUTHOR

Jason Earls, Nov 20 2002

STATUS

approved

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Last modified February 6 20:45 EST 2023. Contains 360111 sequences. (Running on oeis4.)