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a(n) is the largest integer that makes A237354(a(n))=n.
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%I #11 Oct 02 2014 23:01:16

%S 2,3,7,23,89,389,2297,13903,82829,508847

%N a(n) is the largest integer that makes A237354(a(n))=n.

%C a(0)-a(7) are primes, while a(8) = 113*733. Probably, a(9) = 508847 and a(10) = 3699977. - _Giovanni Resta_, Feb 23 2014

%C Probably, a(11) = 28644529 and a(12) = 235037603. - _Hiroaki Yamanouchi_, Oct 02 2014

%e A237354(2)=0 and this is the only 0 in A237354. So a(0)=2;

%e A237354(3)=1 and this is the only 1 in A237354. So a(1)=3;

%e A237354(4,5,6,7)=2, the largest one is A237354(7). So a(2)=7;

%e There are 10 numbers between (include) 8 and 23 that make A237354(n)=3. The largest one is 23. There is no more A237354(n)=3 checked up to n=2*3*5+1=31. So a(3)=23;

%e Checked up to n=2*3*5*7+1=211, we got a(4)=89;

%e Checked up to n=2*3*5*7*11+1=2311, we got a(5)=389;

%e Checked up to n=2*3*5*7*11*13+1=30031, we got a(6)=2297;

%Y Cf. A237354.

%K nonn,hard,more

%O 0,1

%A _Lei Zhou_, Feb 06 2014

%E a(8) from _Giovanni Resta_, Feb 23 2014

%E a(9) from _Hiroaki Yamanouchi_, Oct 02 2014