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A082880 Largest value of A075860(j) when j runs through composite numbers between n-th and (n+1)-th primes. That is, the largest fixed-point[=prime] reached by iteration of A008472(=sum of prime factors) initiated with composite values between two consecutive primes. 3

%I

%S 0,2,5,7,5,3,5,13,5,7,19,7,5,13,7,31,7,7,19,5,7,43,13,19,7,13,2,5,7,

%T 61,7,19,3,73,7,7,7,43,13,19,7,13,5,7,2,103,109,3,5,31,61,7,13,19,13,

%U 31,7,139,19,2,73,151,7,5,3,43,13,31,19,13,181,19,13,7,193,23,199,29,103,73

%N Largest value of A075860(j) when j runs through composite numbers between n-th and (n+1)-th primes. That is, the largest fixed-point[=prime] reached by iteration of A008472(=sum of prime factors) initiated with composite values between two consecutive primes.

%F a(n)=Max[A075860(x); x=1+p(n), ..., -1+p(n+1)]

%t ffi[x_] := Flatten[FactorInteger[x]] lf[x_] := Length[FactorInteger[x]] ba[x_] := Table[Part[ffi[x], 2*w-1], {w, 1, lf[x]}] sopf[x_] := Apply[Plus, ba[x]] Table[Max[Table[FixedPoint[sopf, w], {w, 1+Prime[n], Prime[n+1]-1}]]

%Y Cf. A075860, A008472, A082087, A082088, A082881, A029908.

%K nonn

%O 1,2

%A _Labos Elemer_, Apr 16 2003

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Last modified March 28 13:21 EDT 2020. Contains 333089 sequences. (Running on oeis4.)