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 A213317 #7 Sep 01 2012 11:48:57 %S A213317 1000,1001,1004,1006,1008,1040,1044,1046,1048,1060,1064,1066,1068, %T A213317 1080,1081,1084,1086,1088,1400,1404,1406,1408,1440,1444,1446,1448, %U A213317 1460,1464,1466,1468,1469,1480,1484,1486,1488,1600 %N A213317 Numbers with exactly 10 nonprime substrings (substrings with leading zeros are considered to be nonprime). %C A213317 The sequence is finite. Proof: Each 9-digit number has at least 15 nonprime substrings. Thus, each number with more than 9 digits has >= 15 nonprime substrings, too. Consequently, there is a boundary b<10^9, such that all numbers > b have more than 10 nonprime substrings. %C A213317 The first term is a(1)=1000=A213302(10). The last term is a(20230)=37337397=A213300(10). %H A213317 Hieronymus Fischer, <a href="/A213317/b213317.txt">Table of n, a(n) for n = 1..20230</a> %e A213317 a(1)=1000, since 1000 has 10 nonprime substrings (0, 0, 0, 1, 00, 00, 10, 000, 100, 1000). %e A213317 a(20230)= 37337397, since there are 10 nonprime substrings (9, 33, 39, 7337, 7397, 73373, 373373, 733739, 7337397, 37337397). %Y A213317 Cf. A019546, A035232, A039996, A046034, A069489, A085823, A211681, A211682, A211684, A211685. %Y A213317 Cf. A035244, A079307, A213300 - A213321. %K A213317 nonn,fini,base %O A213317 1,1 %A A213317 _Hieronymus Fischer_, Aug 26 2012