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 A068172 #7 Jul 29 2022 21:13:56 %S A068172 7,17,107,1087,10487,104087,1024087,10024087,100024087,1000124087, %T A068172 10001240087,100012400837,1000124008327,10000124008327, %U A068172 100001124008327,1000011224008327,10000110224008327,100001100224008327,1000010100224008327,10000101002240083271,100001010022400283271,1000010100221400283271 %N A068172 Define an increasing sequence as follows. Given the first term called the seed (the seed need not have the property of the sequence.). Subsequent terms are defined as obtained by inserting/placing digits (at least one) in the previous term to obtain the smallest number with a given property. This is the growing prime sequence for the seed a(1) = 7. %H A068172 Alois P. Heinz, <a href="/A068172/b068172.txt">Table of n, a(n) for n = 1..300</a> %e A068172 The primes obtained by inserting/placing a digit in a(2) = 17 are 107,127, 137, etc...a(3) = 107 is the smallest. %Y A068172 Cf. A068166, A068167, A068169, A068170, A068171. %K A068172 base,nonn %O A068172 1,1 %A A068172 _Amarnath Murthy_, Feb 25 2002 %E A068172 More terms from _Robert Gerbicz_, Sep 06 2002