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Numbers that are the sum of two consecutive semiprimes and also the sum of two consecutive 3-almost primes.
1

%I #36 Jun 11 2021 19:19:23

%S 47,95,115,134,151,201,233,285,301,335,346,368,461,513,527,541,576,

%T 640,713,787,801,810,864,907,935,944,1104,1160,1225,1245,1255,1360,

%U 1397,1471,1513,1521,1574,1620,1692,1740,1775,1782,1831,1867,1873,1913,1967,2009

%N Numbers that are the sum of two consecutive semiprimes and also the sum of two consecutive 3-almost primes.

%C Apparently the sequence is infinite.

%H Zak Seidov, <a href="/A335076/b335076.txt">Table of n, a(n) for n = 1..26539</a> (all terms up to 10^6).

%e 47 = 22 + 25 = A118717(8) = A001358(8) + A001358(9), and

%e 47 = 20 + 27 = A014612(4) + A014612(5).

%t p[n_, m_] := Plus @@@ Partition[Select[Range[m], PrimeOmega[#] == n &], 2, 1]; m = 1100; Intersection[p[2, m], p[3, m]] (* _Amiram Eldar_, May 24 2020 *)

%Y Cf. A001358, A014612, A118717.

%K nonn

%O 1,1

%A _Zak Seidov_, May 22 2020