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A082086
Fixed points when A001414 is iterated and started at factorials of prime numbers.
2
2, 5, 5, 5, 13, 23, 61, 19, 5, 283, 5, 23, 13, 29, 7, 61, 947, 29, 137, 11, 353, 23, 199, 5, 47, 2381, 5, 103, 359, 13, 5, 5, 7, 5, 47, 19, 577, 7, 5, 29, 5, 5, 5, 41, 11, 23, 239, 7, 11, 5, 11, 5, 23, 11821, 31, 5, 5, 13669, 7, 193, 5, 991, 89, 7, 13, 18199, 131, 113, 20849
OFFSET
1,1
FORMULA
a(n) = A029908(A000142(A000040(n))) = A029908(prime(n)!).
EXAMPLE
n=100, prime(100) = 541, start at 541!, the list is: {541!,...,46374,195,21,10,7} so a(100)=7.
MATHEMATICA
sopfr[n_] := Total[Times @@@ FactorInteger[n]]; a[n_] := FixedPoint[sopfr, Prime[n]!]; Array[a, 100] (* Jean-François Alcover, May 06 2017 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Apr 08 2003
STATUS
approved