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 A281314 #28 Mar 03 2024 10:15:06 %S A281314 4,9,14,21,26,33,38,49,62,65,82,85,122,129,134,141,146,159,166,169, %T A281314 206,209,214,217,254,259,262,265,278,289,302,305,334,339,346,365,382, %U A281314 393,398,403,422,427,446,451,454,471,478,481,542,545 %N A281314 a(1) = 4; a(n) = smallest semiprime such that a(n) - a(n-1) is an odd prime. %C A281314 a(n) >= A175587(n). %C A281314 First differences: 5, 5, 7, 5, 7, 5, 11, 13, 3, 17, 3, 37, 7, 5, 7, 5, 13, 7, 3, 37, 3, 5, 3, 37, 5, 3, 3, 13, 11, 13, 3, 29, 5, 7, 19, 17, 11, 5, 5, 19, 5, 19, 5, 3, 17, 7, 3, 61, 3 (all odd primes). %H A281314 Zak Seidov, <a href="/A281314/b281314.txt">Table of n, a(n) for n = 1..1000</a> %t A281314 NestList[(p = 3; While[2 != PrimeOmega[q = # + p], p = NextPrime[p]]; q) &, 4, 50] %t A281314 nxt[n_]:=Module[{k=n+1},While[PrimeOmega[k]!=2||!PrimeQ[k-n]||EvenQ[k-n],k++];k]; NestList[nxt,4,50] (* _Harvey P. Dale_, Feb 14 2019 *) %Y A281314 Cf. A001358, A017558. %K A281314 nonn %O A281314 1,1 %A A281314 _Zak Seidov_, Jan 25 2017