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 A213310 #7 Sep 01 2012 11:47:56 %S A213310 10,14,16,18,40,44,46,48,49,60,64,66,68,69,80,81,84,86,88,90,91,94,96, %T A213310 98,99,117,123,127,132,133,135,139,153,157,167,171,172,175,177,193, %U A213310 211,213,217,222,225,230,234,236,238,241 %N A213310 Numbers with exactly 3 nonprime substrings (substrings with leading zeros are considered to be nonprime). %C A213310 The sequence is finite. Proof: Each 6-digit number has at least 4 nonprime substrings. Thus, each number with more than 6 digits has >= 4 nonprime substrings, too. Consequently, there is a boundary b<10^5, such that all numbers > b have more than 3 nonprime substrings. %C A213310 The first term is a(1)=10=A213302(3). The last term is a(310)=73373=A213300(3). %H A213310 Hieronymus Fischer, <a href="/A213310/b213310.txt">Table of n, a(n) for n = 1..310</a> %e A213310 a(1)=10, since 10 has 3 nonprime substrings (0, 1, 10). %e A213310 a(310)= 73373, since there are 3 nonprime substrings (33, 7337 and 73373). %Y A213310 Cf. A019546, A035232, A039996, A046034, A069489, A085823, A211681, A211682, A211684, A211685. %Y A213310 Cf. A035244, A079307, A213300 - A213321. %K A213310 nonn,fini,base %O A213310 1,1 %A A213310 _Hieronymus Fischer_, Aug 26 2012