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 A122072 #14 May 24 2013 03:16:08
%S A122072 7,19,29,37,47,59,67,79,89,97,109,113,127,139,149,157,167,179,181,199,
%T A122072 199,211,229,239,241,257,269,277,283,293,307,317,317,337,349,359,367,
%U A122072 379,389,397,409,419,421,439,449,457,467,479,487,499,509,509,523,523
%N A122072 Greatest prime less than 10n.
%C A122072 First repeating terms are 199, 317, 509, 523, 619, 839, 887, 1069, 1129, 1129, 1259, 1327, 1327, 1327, 1409, 1459, 1499, 1637, 1669, 1669, 1709, 1759, 1789, 1847, 1889, 1913, 1951.
%C A122072 a(n) is also the greatest prime factor among composites (A002808) below 20n. For primes of the form 20n + 1, see A141881. - Lekraj Beedassy, Jan 23 2012
%H A122072 Charles R Greathouse IV, <a href="/A122072/b122072.txt">Table of n, a(n) for n = 1..10000</a>
%t A122072 Table[Prime[PrimePi[10 n]], {n, 54}] (* _Jayanta Basu_, May 24 2013 *)
%o A122072 (PARI) a(n)=precprime(10*n) \\ _Charles R Greathouse IV_, Feb 26 2012
%K A122072 nonn,easy
%O A122072 1,1
%A A122072 _Zak Seidov_, Oct 16 2006