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The average of primes dividing n and n+1 is the same.
2

%I #5 Jul 26 2013 11:24:15

%S 459,2023,5063,11111,87615,92080,224720,268191,390224,524799,535601,

%T 680096,758848,1144375,1235168,1303169,1319297,1366000,1525568,

%U 2570291,2985620,3085874,3090969,3297096,4100071,4507524,5695742,5812158,5869968,6324725,6540544

%N The average of primes dividing n and n+1 is the same.

%C Up to 10^13 there are no consecutive numbers in the sequence.

%H Giovanni Resta, <a href="/A227754/b227754.txt">Table of n, a(n) for n = 1..1000</a>

%e 87615 is in the sequence because 87615 = 3^3*5*11*59, 87616 = 2^6*37^2 and (3+5+11+59)/4 = (2+37)/2.

%t avep[n_] := Mean[First /@ FactorInteger[n]]; Select[Range[2,10^5], avep[#] == avep[#+1] &]

%Y Cf. A227755.

%K nonn,easy

%O 1,1

%A _Giovanni Resta_, Jul 26 2013