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 A277442 #21 Nov 20 2016 11:28:59 %S A277442 0,10,101,100,10006,950005,1001,9569005,100105,100500,1000,95370001, %T A277442 1000201,102100005,9957800,100006,9500005,1100005,100100,1010005, %U A277442 10001,10000096,10005005,1000105,1001005,999578000,1002600005,12500100,100010505,1050500005,1000500 %N A277442 Least number k such that k^2 can be obtained from k by inserting internal (but not necessarily contiguous) digits in n different ways. %C A277442 a(6) = 1001. %H A277442 Lars Blomberg, <a href="/A277442/b277442.txt">Table of n, a(n) for n = 0..157</a> %e A277442 a(2) = 101 as 101 is the least number that can be modified in two different ways in order to become its square; i.e., 101^2 equals 10201, which can be represented as 1(02)01 or 10(20)1. %e A277442 a(5) = 950005 because 950005^2 = 902509500025 can be represented in 5 ways: 9(02)5(095)000(2)5, 9(02)50(95)0(0)0(2)5, 9(02)50(95)00(02)5, 9(02)50(950)00(2)5, 9(02509)5000(2)5. %Y A277442 Cf. A046851, A277441. %K A277442 base,nonn %O A277442 0,2 %A A277442 _Ivan N. Ianakiev_, Oct 15 2016 %E A277442 Terms a(5), a(7) and beyond from _Lars Blomberg_, Nov 20 2016