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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
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, 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, 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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..80.

FORMULA

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

MATHEMATICA

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}]]

CROSSREFS

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

Sequence in context: A138320 A199275 A135007 * A257321 A011038 A079378

Adjacent sequences:  A082877 A082878 A082879 * A082881 A082882 A082883

KEYWORD

nonn

AUTHOR

Labos Elemer, Apr 16 2003

STATUS

approved

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Last modified February 26 21:27 EST 2020. Contains 332295 sequences. (Running on oeis4.)