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 A090342 Difference between the sums of the prime factors, including multiplicity, of n and those of n + 3. 4

%I

%S -4,-3,-2,-3,-1,-1,0,-5,-1,-6,2,-1,5,-8,0,-11,8,-2,6,-14,1,3,8,0,-1,

%T -14,-1,-20,19,-4,12,-2,4,-18,-9,-6,26,-20,4,-32,26,1,18,-32,0,11,35,

%U -9,-3,-41,9,1,40,-11,-15,-46,10,-30,26,-1,49,15,-3,-55,-3,-10,53,-50,14,-59,32,-1,50,21,-5,-56,5,6,36,-70,-2,21,38

%N Difference between the sums of the prime factors, including multiplicity, of n and those of n + 3.

%H Harvey P. Dale, <a href="/A090342/b090342.txt">Table of n, a(n) for n = 1..1000</a>

%F a(n) = A001414(n) - A001414(n+3). - _Wesley Ivan Hurt_, Aug 29 2016

%e a(24)=0 because 24=2*2*2*3, 27=3*3*3 and (2+2+2+3)-(3+3+3)=0.

%t Join[{-4},#[[1]]-#[[4]]&/@(Partition[Table[Total[Flatten[Table[#[[1]], #[[2]]]&/@ FactorInteger[n]]],{n,2,90}],4,1])] (* _Harvey P. Dale_, Sep 16 2018 *)

%Y Cf. A001414, A090340, A090341, A090343.

%K sign

%O 1,1

%A Charles K. Layman (cklayman(AT)juno.com), Nov 25 2003

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Last modified August 14 09:14 EDT 2020. Contains 336480 sequences. (Running on oeis4.)