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 A062095 #9 Mar 22 2023 08:15:31 %S A062095 1,11,111,337,1337,7191,51141,317047,1317047,2814687,9312743,25193697, %T A062095 30981533,51496017,192326779,1427134777,4987286171,6471777063, %U A062095 61653104971,259323776747,737046253821,7171027958513,31727922601647 %N A062095 a(1) = 1, a(n) = concatenation of two closest factors of a(n-1) whose product equals a(n-1) or if a(n-1) is a prime then the concatenation of 1 and a(n-1). %H A062095 Sean A. Irvine, <a href="/A062095/b062095.txt">Table of n, a(n) for n = 1..250</a> %e A062095 a(3) = 111 hence a(4) = 337, as 3*37 = 111 and 3 < 37. %t A062095 f[n_Integer] := (d = Divisors[n]; l = Length[d]; If[ EvenQ[l], ToExpression[ ToString[ d[[l/2]] ] <> ToString[ d[[l/2 + 1]] ]], ToExpression[ ToString[d[[l/2 + .5]] ] <> ToString[ d[[l/2 + .5]] ]]] ); NestList[f, 1, 25] %Y A062095 Cf. A062094, A003681. %K A062095 nonn,easy,base %O A062095 1,2 %A A062095 _Amarnath Murthy_, Jun 16 2001 %E A062095 More terms from _Robert G. Wilson v_, Aug 08 2001