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 A090343 Difference between the sums of the prime factors, including multiplicity, of n and those of n + 4. 3

%I #8 Jul 02 2022 17:43:05

%S -5,-3,-4,-2,-1,-2,-4,-1,-7,-2,3,-1,-4,1,-11,-1,7,-5,-4,0,0,-2,14,-2,

%T -19,5,-22,1,15,-9,19,0,-23,-2,-4,-1,-4,9,-27,-4,30,-13,-4,4,-3,13,27,

%U -6,-39,1,4,4,31,-20,-43,1,-39,-2,46,0,43,17,-54,-9,-8,2,-4,9,-47,-25,58,-11,55,21,-66,10,6,-25,-4,-1,-10,-2,51,-3,-67

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

%F a(n) = A001414(n) - A001414(n+4). - _Wesley Ivan Hurt_, Aug 29 2016

%e a(24)=-2 because 24=2*2*2*3, 28=2*2*7 and (2+2+2+3)-(2+2+7)=-2.

%t Join[{-5},#[[1]]-#[[5]]&/@Partition[Table[Total[Times@@@FactorInteger[n]],{n,2,90}],5,1]] (* _Harvey P. Dale_, Jul 02 2022 *)

%Y Cf. A001414, A090340, A090341, A090342.

%K sign

%O 1,1

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

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Last modified June 6 14:05 EDT 2023. Contains 363147 sequences. (Running on oeis4.)