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a(n) is the result of beginning with n and iterating k -> A064916(k) until a prime is reached.
4

%I #14 Jun 19 2018 05:14:56

%S 2,3,3,5,3,7,5,5,3,11,7,13,5,7,5,17,3,19,11,5,7,23,13,5,5,11,7,29,5,

%T 31,17,13,3,11,19,37,11,7,5,41,7,43,23,17,13,47,5,13,5,19,11,53,7,7,

%U 29,5,5,59,31,61,17,23,13,17,3,67,11,5,19,71,37,73,11,11,7,17,5,79,41,29,7

%N a(n) is the result of beginning with n and iterating k -> A064916(k) until a prime is reached.

%C Well-defined since A064916(n) < n for nonprimes.

%C a(p) = p for all primes p.

%H Harry J. Smith, <a href="/A064917/b064917.txt">Table of n, a(n) for n = 2..1000</a>

%H Michael Gilleland, <a href="/selfsimilar.html">Some Self-Similar Integer Sequences</a>

%e a(6) = 3 as A064916(6) = 4 and A064916(4) = 3.

%o (PARI) lpf(n)= { local(f); f=factor(n); return(f[1, 1]) } { for (n=2, 1000, m=n; while (!isprime(m), L=lpf(m); m=m / L + L - 1); write("b064917.txt", n, " ", m) ) } \\ _Harry J. Smith_, Sep 29 2009

%Y Cf. A064916, A064918, A064921.

%K nonn

%O 2,1

%A _Reinhard Zumkeller_, Oct 14 2001