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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.

%I A073938 #12 Dec 08 2019 12:24:16
%S A073938 153,3009,3288,5170,5364,11186,11295,11395,12874,13545,16288,17892,
%T A073938 27760,28118,34187,38907,47650,55282,63455,64972,65290,95886,104718,
%U A073938 106793,110944,155573,163964,169644,172081,187164,202607,203255,204609
%N 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.
%C A073938 Are there infinitely many k-tuples in A078142?
%H A073938 Amiram Eldar, <a href="/A073938/b073938.txt">Table of n, a(n) for n = 1..5000</a>
%t A073938 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 *)
%Y A073938 Cf. A071247, A078142.
%K A073938 nonn
%O A073938 1,1
%A A073938 _Jason Earls_, Nov 20 2002