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%I #14 Sep 20 2022 02:39:11
%S 4,27,208,18630,780856896
%N a(1)=4; a(n) is the smallest number m > a(n-1) such that Omega(m + a(i)) = Omega(m) - Omega(a(i)) for i = 1..(n-1) where Omega(k) is the number of prime divisors of k counted with multiplicity.
%C Conjecture: Omega(a(n)) = n-th prime.
%C The conjecture is false because Omega(780856896) = 10. - _Sean A. Irvine_, Sep 19 2022
%C Next term > 10000000000. - _Sean A. Irvine_, Sep 20 2022
%Y Cf. A001222, A059333, A059363.
%K nonn,hard,more
%O 1,1
%A _Naohiro Nomoto_, Jan 29 2001
%E Name simplified and a(5) from _Sean A. Irvine_, Sep 19 2022
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