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 A050806 #12 Oct 17 2019 22:54:58
%S A050806 101,149,163,241,269,271,317,347,367,397,409,419,443,487,509,541,587,
%T A050806 601,641,761,787,811,821,863,907,919,1439,1481,1663,1877,2089,2111,
%U A050806 2579,2593,2671,2819,2971,3121,3457,3463,3571,3643,3659,3769,3917,4001
%N A050806 Inserting any digit between adjacent digits of prime p produces exactly 1 new prime.
%H A050806 Reinhard Zumkeller, <a href="/A050806/b050806.txt">Table of n, a(n) for n = 1..10000</a>
%e A050806 101 yields only one prime using digit '6' -> 1(6)0(6)1 -> prime 16061.
%t A050806 aQ[n_]:=Plus@@Boole[PrimeQ[Table[FromDigits[Riffle[IntegerDigits[n],k]],{k,0,9}]]]==1; Select[Prime[Range[5,555]],aQ[#]&] (* _Jayanta Basu_, May 30 2013 *)
%o A050806 (Haskell)
%o A050806 import Data.List (intersperse)
%o A050806 a050806 n = a050806_list !! (n-1)
%o A050806 a050806_list = filter ((== 1) . sum . f) a000040_list where
%o A050806 f p = map (i $ show p) "0123456789"
%o A050806 i ps d = a010051' (read $ intersperse d ps :: Integer)
%o A050806 -- _Reinhard Zumkeller_, May 07 2013
%Y A050806 Cf. A050674-A050719, A050805.
%Y A050806 Cf. A010051, A000040.
%K A050806 nonn,base
%O A050806 1,1
%A A050806 _Patrick De Geest_, Oct 15 1999
%E A050806 Offset corrected by _Reinhard Zumkeller_, May 07 2013