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%I #14 Nov 27 2020 04:50:03
%S 1,5,7,22,15,33,23,49,88,35,114,79,48,100,148,189,57,201,139,78,230,
%T 158,269,370,192,102,215,112,211,803,259,390,150,666,147,430,471,317,
%U 485,506,152,869,168,364,184,1144,1213,404,206,433,613,217,1134,702,720,712
%N Number of semiprimes between two primes squared.
%F a(n) = A217019(n) - 1. - _Flávio V. Fernandes_, Nov 19 2020
%p A165144 := proc(n) a := 0 ; for k from ithprime(n)^2+1 to ithprime(n+1)^2-1 do if numtheory[bigomega](k) = 2 then a := a+1 ; fi ; end do ; a ; end proc: seq(A165144(n),n=1..80) ; # _R. J. Mathar_, Jan 30 2010
%Y Cf. A001248 (primes squared), A001358 (semiprimes), A217019.
%K nonn
%O 1,2
%A _Giovanni Teofilatto_, Sep 05 2009
%E a(7) corrected and terms beyond a(7) added by _R. J. Mathar_, Jan 30 2010
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