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%I #9 Jan 13 2019 13:37:32
%S 10,15,25,34,46,51,55,57,69,86,91,95,106,119,121,133,141,145,155,161,
%T 166,217,218,226,247,249,253,262,274,291,298,299,302,305,341,358,365,
%U 382,407,413,445,446,481,485,501,515,533,538,543,551,559,614,623,626
%N Sum of a semiprime and its semiprime index is a new semiprime.
%C This is the semiprime analog of A061067.
%H Eric Weisstein, World of Mathematics, <a href="http://mathworld.wolfram.com/Semiprime.html">Semiprime.</a>
%F a(n) = A100466(n) - A100915(n) = A001358(A100915(n)).
%e a(1) = 10 because 10 = semiprime(4) and semiprime(4) + 4 = 14 is
%e semiprime.
%e a(2) = 15 because 15 = semiprime(6) and semiprime(6) + 6 = 21 is
%e semiprime.
%t Module[{sp=Select[Range[1000],PrimeOmega[#]==2&],len},len=Length[sp];Select[ Thread[{sp,Range[len]}],PrimeOmega[Total[#]]==2&]][[All,1]] (* _Harvey P. Dale_, Jan 13 2019 *)
%Y Cf. A001358, A061067, A100493, A100466, A100467, A100915.
%K easy,nonn
%O 1,1
%A _Ray Chandler_, Nov 26 2004
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