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%I #11 Oct 08 2024 07:19:29
%S 1,2,6,10,25,26,60,74,78,115,122,123,140,145,146,147,153,156,169,186,
%T 195,205,207,220,222,231,245,253,259,273,314,323,325,341,345,348,355,
%U 361,369,386,387,427,438,453,473,481,505,507,529,536,537,553,554,555,559,561,573,582,618,620,626,635
%N Numbers k such that Omega(k + Omega(k)) = Omega(k) + Omega(Omega(k)), where Omega = A001222.
%C Includes semiprimes k such that k + 2 is a triprime.
%H Robert Israel, <a href="/A376843/b376843.txt">Table of n, a(n) for n = 1..10000</a>
%e a(5) = 25 is a term because Omega(25) = 2, Omega(2) = 1 and Omega(25 + 2) = Omega(27) = 3 = 2 + 1.
%p filter:= proc(k) uses numtheory; local s;
%p s:= bigomega(k);
%p bigomega(k+s) = s + bigomega(s)
%p end proc:
%p select(filter, [$1..1000]);
%Y Cf. A001222, A001358, A014612, A376830, A376831, A376844, A376848, A376849, A376851.
%K nonn
%O 1,2
%A _Robert Israel_, Oct 06 2024