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 A242490 #22 May 30 2014 09:17:25
%S A242490 6,8,80,14,224,20,440,854,32,1460,1742,44,2282,3434,4190,62,5432,4760,
%T A242490 74,12194,8930,8054,12374,13292,104,15350,110,14282,31982,17402,18212,
%U A242490 140,24050,152,25220,29990,28202,32234,33392,182,43262,194,44972,200,47564
%N A242490 Smallest even number k such that lpf(k-3) = prime(n) while lpf(k-1) > lpf(k-3), where lpf=least prime factor (A020639).
%C A242490 Note that the "small terms" {6,8,14,20,32,44,...} correspond to a(n) for which {a(n)-3, a(n)-1} is a twin pair such that the corresponding positions form sequence A029707.
%C A242490 If we change the definition to consider k for which {k-3, k-1} is not a twin pair, we obtain a closely related sequence 12,38,80,212,224,530,440,854,1250,1460,1742,... which shows a "model behavior" of A242490, if there are only a finite number of twin primes. - _Vladimir Shevelev_, May 19 2014
%H A242490 Peter J. C. Moses, <a href="/A242490/b242490.txt">Table of n, a(n) for n = 2..1001</a>
%e A242490 Let n=2, prime(2)=3. Then lpf(6-3)=3, but lpf(6-1)=5>3. Since k=6 is the smallest such k, a(2)=6.
%o A242490 (PARI) a(n)=my(p=prime(n),k=p+3); while(factor(k-3)[1,1]<p || factor(k-1)[1,1]<p, k += 2*p); k \\ _Charles R Greathouse IV_, May 30 2014
%Y A242490 Cf. A001359, A006512, A242489.
%K A242490 nonn
%O A242490 2,1
%A A242490 _Vladimir Shevelev_, May 16 2014
%E A242490 Correction and more terms from _Peter J. C. Moses_, May 19 2014