This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A106550 #19 Feb 18 2024 09:06:52
%S A106550 26,29,42,35,41,50,58,233,80,239,344,251,92,257,352,269,126,368,566,
%T A106550 376,287,293,578,392,311,788,323,602,329,416,804,424,341,614,359,448,
%U A106550 638,377,836,1232,383,464,472,852,401,488,413,1256,674,419,686,437,512,884
%N A106550 a(n) = n-th semiprime + (concatenation of its two prime factors, smallest factor first).
%F A106550 a(n) = A001358(n) + A106554(n). - _Reinhard Zumkeller_, May 19 2005
%e A106550 First semiprime is 4; 4 is 2*2; 26=4+22.
%e A106550 Second semiprime is 6; 6 is 2*3; 29=6+23.
%e A106550 Third semiprime is 9; 9 is 3*3; 41=9+33.
%e A106550 Fourth semiprime is 10; 10 is 2*5; 35=10+25.
%t A106550 R=165;SP=Select[Range[R], PrimeOmega[#]==2&]; FromDigits@ Flatten[IntegerDigits@ Table[#1, {#2}] & @@@ FactorInteger@ #] & /@ SP +SP (* _James C. McMahon_, Feb 18 2024 *)
%Y A106550 Cf. A084126, A084127, A001358, A106554.
%K A106550 base,easy,nonn
%O A106550 1,1
%A A106550 _Eric Angelini_, May 09 2005
%E A106550 More terms from _Reinhard Zumkeller_, May 19 2005
%E A106550 Typo corrected by _James C. McMahon_, Feb 06 2024