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Amiram Eldar, <a href="/A074592/b074592_1.txt">Table of n, a(n) for n = 1..10000</a>
reviewed
approved
proposed
reviewed
editing
proposed
Amiram Eldar, <a href="/A074592/b074592_1.txt">Table of n, a(n) for n = 1..10000</a>
s[n_] := Module[{f = FactorInteger[n]}, If[Length[f] > 1, f[[1, 1]], Nothing]]; Array[s, 200] (* Amiram Eldar, Oct 10 2024 *)
approved
editing
_Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), _, Aug 25 2002
nonn,new
nonn
Reinhard Zumkeller (reinhard.zumkeller(AT)lhsystemsgmail.com), Aug 25 2002
Smallest prime factors of numbers that are not prime powers.
2, 2, 2, 2, 3, 2, 2, 3, 2, 2, 2, 2, 2, 3, 2, 5, 2, 2, 3, 2, 2, 2, 3, 2, 2, 2, 3, 2, 2, 5, 2, 3, 2, 2, 2, 3, 5, 2, 2, 3, 2, 2, 2, 3, 2, 7, 2, 2, 2, 2, 5, 2, 3, 2, 2, 7, 2, 3, 2, 5, 2, 2, 3, 2, 2, 2, 3, 2, 2, 2, 3, 2, 2, 5, 2, 3, 2, 7, 2, 2, 3, 2, 2, 3, 2, 2, 7, 2, 3, 2, 2, 2, 3, 2, 11, 2, 5, 2, 3, 2, 2, 2, 3, 2
1,1
a(n)>2 iff n+1 and n+2 are prime powers (A006549).
nonn
Reinhard Zumkeller (reinhard.zumkeller(AT)lhsystems.com), Aug 25 2002
approved