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 A157487 #12 Sep 10 2022 14:35:06
%S A157487 10529,15391,17983,18751,22049,23489,24751,26081,29249,32561,35153,
%T A157487 43471,49951,52975,58049,58481,67229,67231,70687,71873,72415,76049,
%U A157487 77921,79001,79649,82783,83249,85751,88289,93799,95551,97471,102545
%N A157487 Numbers k such that k-1 and k+1 are each the product of exactly 7 primes, counted with multiplicity.
%H A157487 Harvey P. Dale, <a href="/A157487/b157487.txt">Table of n, a(n) for n = 1..3000</a>
%p A157487 with(numtheory): a := proc (n) if bigomega(n-1) = 7 and bigomega(n+1) = 7 then n else end if end proc: seq(a(n), n = 2 .. 120000); # _Emeric Deutsch_, Mar 07 2009
%t A157487 q=7;lst={};Do[If[Plus@@Last/@FactorInteger[n-1]==q&&Plus@@Last/@FactorInteger[n+1]==q,AppendTo[lst,n]],{n,9!}];lst
%t A157487 Select[Range[110000],PrimeOmega[#+{1,-1}]=={7,7}&] (* _Harvey P. Dale_, Apr 04 2015 *)
%t A157487 Mean/@SequencePosition[PrimeOmega[Range[105000]],{7,_,7}] (* _Harvey P. Dale_, Sep 10 2022 *)
%Y A157487 Cf. A124936, A014612, A157483, A157484, A157485, A157486.
%K A157487 nonn
%O A157487 1,1
%A A157487 _Vladimir Joseph Stephan Orlovsky_, Mar 01 2009
%E A157487 More terms from _Emeric Deutsch_, Mar 07 2009