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%I #28 May 01 2014 01:49:17
%S 1,2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,
%T 89,97,101,103,107,109,113,127,131,137,139,149,151,157,163,167,173,
%U 179,181,191,193,197,199,211,223,227,229,233,239,241,251,257,263,269,271,277,281,283,293,307,311,319,317
%N a(n) = max { k | A064553(k) = n }.
%C a(n+1) = A000040(n) for 1 < n < 66, but A000040(65) = 313 <> 319 = 11*29 = a(66).
%C In the plot, the lowest line corresponds to the cases when a(n)=prime(n-1). - _T. D. Noe_, Dec 12 2004
%C a(n) = A080688(n,A001055(n)). - _Reinhard Zumkeller_, Oct 01 2012
%H T. D. Noe, <a href="/A064555/b064555.txt">Table of n, a(n) for n = 1..8000</a>
%F A064553(a(n)) = n and A064553(a(k)) <> k for k > a(n).
%t (* b = A064553 *) nmax = 67; b[1] = 1; b[p_?PrimeQ] := b[p] = PrimePi[p] + 1; b[n_] := b[n] = b[p = FactorInteger[n][[1, 1]]]*b[n/p]; bb = Table[{k, b[k]}, {k, 1, 4*Prime[nmax]}]; A064555 = Max[#[[All, 1]]]& /@ Split[ Sort[bb, #1[[2]] < #2[[2]] &], #1[[2]] == #2[[2]]&]; a[n_] := A064555[[n]]; Table[a[n], {n, 1, nmax}] (* _Jean-François Alcover_, Sep 04 2012 *)
%o (Haskell)
%o a064555 = last . a080688_row -- _Reinhard Zumkeller_, Oct 01 2012
%Y Cf. A064554, A001055, A064553, A000040.
%K nonn,look
%O 1,2
%A _Reinhard Zumkeller_, Sep 21 2001
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