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 A180117 #25 Sep 20 2020 02:21:23
%S A180117 18,28,42,50,66,68,76,114,170,172,186,188,236,242,244,266,273,282,284,
%T A180117 290,316,343,354,385,402,404,410,423,426,428,434,436,475,506,596,602,
%U A180117 603,604,637,652,663,668,722,762,775,786,788,845,890,892,906,925,962
%N A180117 Numbers n such that n and n+2 are both divisible by exactly 3 primes (counted with multiplicity).
%C A180117 Numbers k such that both k and k + 2 are in A014612.
%H A180117 Harvey P. Dale, <a href="/A180117/b180117.txt">Table of n, a(n) for n = 1..1000</a>
%e A180117 a(1) = 18 because 18 = 2*3*3 and 18+2 = 20 = 2*2*5 both have 3 prime divisors, counted with multiplicity.
%e A180117 a(2) = 28 because 28 = 2*2*7 and 28+2 = 30 = 2*3*5 both have 3 prime divisors, counted with multiplicity.
%t A180117 #[[1,1]]&/@(Select[Partition[Table[{n,PrimeOmega[n]},{n,1000}],3,1], #[[1,2]]==#[[3,2]]==3&]) (* _Harvey P. Dale_, Oct 20 2011 *)
%t A180117 SequencePosition[PrimeOmega[Range[1000]],{3,_,3}][[All,1]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Apr 08 2017 *)
%o A180117 (PARI) is(n)=bigomega(n)==3 && bigomega(n+2)==3 \\ _Charles R Greathouse IV_, Jan 31 2017
%Y A180117 Cf. A001359, A014612.
%K A180117 easy,nonn
%O A180117 1,1
%A A180117 _Jonathan Vos Post_, Aug 10 2010
%E A180117 More terms from _R. J. Mathar_, Aug 13 2010