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Semiprimes that are the sum of two successive semiprimes.
13

%I #10 Jan 19 2019 17:45:54

%S 10,15,51,69,77,85,95,106,115,134,143,159,178,187,201,217,226,237,262,

%T 267,291,301,327,335,346,355,361,381,395,403,411,415,422,427,437,447,

%U 502,527,565,586,597,614,623,633,649,669,674,687,713,723,758,763,789

%N Semiprimes that are the sum of two successive semiprimes.

%H Zak Seidov, <a href="/A092192/b092192.txt">Table of n,a(n) for n=1..10000</a>.

%e 51 is a member because 51=25+26, sum of 9th and 10th semiprimes.

%t Select[Total/@Partition[Select[Range[400],PrimeOmega[#]==2&],2,1], PrimeOmega[ #]==2&] (* _Harvey P. Dale_, Jan 19 2019 *)

%Y Cf. A092191.

%K easy,nonn

%O 1,1

%A _Zak Seidov_, Feb 23 2004