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%I #18 Jul 07 2024 21:03:09
%S 4,6,14,15,26,35,38,49,51,62,65,74,85,86,91,94,111,121,122,129,134,
%T 158,159,169,183,185,187,201,206,209,215,219,221,237,247,254,287,301,
%U 302,303,305,319,321,326,329,365,371,377,386,403,411,417,427,446,447,458
%N Numbers m such that m and its 10's complement are both semiprimes, i.e., m and 10^k - m, where k is the number of digits of m, are semiprime.
%H Robert Israel, <a href="/A094298/b094298.txt">Table of n, a(n) for n = 1..10000</a>
%e 201 is a term because both 201 and 1000 - 201 = 799 are semiprimes.
%p tc:= n -> 10^(1+ilog10(n))-n:
%p filter:= proc(n) numtheory:-bigomega(n)=2 and numtheory:-bigomega(tc(n))=2 end proc:
%p select(filter, [$1..1000]); # _Robert Israel_, Jul 02 2024
%t Select[Range[500],PrimeOmega[#]==PrimeOmega[10^IntegerLength[#]-#]==2&] (* _Harvey P. Dale_, Jan 17 2013 *)
%Y Cf. A001358, A089186.
%K easy,nonn,base
%O 1,1
%A _Jason Earls_, Jun 02 2004
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