%I #31 Oct 16 2022 03:24:31
%S 1,2,3,7,11,43,53,613367,613439,613451,613523,613549,613609,
%T 6384425461,6384425521,6384425569,6384425647
%N Numbers k such that k divides the k-th semiprime.
%C Note that except 1, all other term in the sequence will be primes.
%C a(18) > 10^12. - _Lucas A. Brown_, Oct 17 2020
%H Lucas A. Brown, <a href="https://github.com/lucasaugustus/oeis/blob/main/semiprimemods.py">semiprimemods.py</a>
%e a(4)=7 is a term because 7 divides the 7th semiprime (i.e., 21).
%Y Cf. A001358, A356764, A357741.
%K nonn,hard,more
%O 1,2
%A _Shyam Sunder Gupta_, May 07 2005
%E a(14)-a(17) from _Donovan Johnson_, Sep 27 2010
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