A119320 - OEIS

%I #15 Sep 18 2021 09:05:16

%S 1,5,2,2,2,3,2,3,9,3,3,3,11,3,2,6,11,7,9,17,3,3,11,3,3,17,5,5,9,33,11,

%T 17,17,3,11,41,39,11,29,7,11,6,21,11,17,17,9,17,11,7,11,83,49,3,2,11,

%U 3,38,23,7,11,14,9,33,3,11,11,11,31,66,9,47,21,17,29

%N Difference between 10^n and the largest n-digit semiprime.

%H Amiram Eldar, <a href="/A119320/b119320.txt">Table of n, a(n) for n = 1..100</a>

%F a(n) = 10^n - A098450(n).

%o (PARI) a(n) = my(k=10^n-1); while (bigomega(k) != 2, k--); 10^n - k; \\ _Michel Marcus_, Sep 18 2021

%Y Cf. A098450.

%K base,nonn

%O 1,2

%A _Zak Seidov_, May 14 2006

%E More terms from _Amiram Eldar_, Sep 18 2021