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A082881 Least value of A075860(j) when j runs through composite numbers between n-th and (n+1)-th primes. That is, the smallest fixed-point[=prime] reached by iteration of function A008472(=sum of prime factors) initiated with composite values between two consecutive primes. 1
0, 2, 5, 2, 5, 2, 5, 7, 2, 7, 2, 2, 5, 2, 2, 2, 7, 2, 2, 5, 2, 3, 2, 5, 3, 13, 2, 5, 3, 2, 2, 2, 3, 2, 7, 5, 3, 13, 2, 3, 7, 2, 5, 3, 2, 2, 2, 2, 5, 7, 2, 7, 2, 2, 2, 2, 7, 2, 3, 2, 2, 2, 2, 5, 2, 2, 5, 2, 19, 2, 2, 2, 5, 2, 2, 3, 2, 3, 2, 2, 17, 2, 5, 5, 2, 2, 2, 7, 23, 2, 2, 3, 3, 3, 5, 2, 2, 19, 2, 5, 2, 3, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..103.

FORMULA

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

EXAMPLE

Between p(23)=83 and p(24)=89, the relevant fixed points are

{5,13,2,2,13}, of which the smallest is 2=a(24).

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[Min[Table[FixedPoint[sopf, w], {w, 1+Prime[n], Prime[n+1]-1}]]

CROSSREFS

Cf. A075860, A008472, A082087, A082088, A082880, A029908.

Sequence in context: A010695 A021400 A059855 * A104289 A309697 A177435

Adjacent sequences:  A082878 A082879 A082880 * A082882 A082883 A082884

KEYWORD

nonn

AUTHOR

Labos Elemer, Apr 16 2003

STATUS

approved

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Last modified March 28 14:24 EDT 2020. Contains 333089 sequences. (Running on oeis4.)