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 A121260 #8 Jun 21 2021 06:24:02 %S A121260 0,0,1,1,2,2,3,3,5,5,7,7,8,8,10,10,11,11,12,12,13,13,14,14,16,16,17, %T A121260 17,18,18,19,19,20,20,21,21,22,22,23,23,24,24,26,26,27,27,28,28,29,29, %U A121260 30,30,31,31,32,32,33,33,34,34,36,36,37,37,38,38,39,39,40,40,41,41,42,42 %N A121260 Beginning with a(1)=0, take a(n) to be the smallest number not equal to the product of two consecutive (not distinct) earlier terms. %C A121260 Apparently the definition is: a(1)=0. For even n, a(n)=a(n-1). For odd n, a(n) is the smallest value > a(n-1) which is not equal to some product a(i)*a(i-1) of two consecutive earlier terms. - _R. J. Mathar_, Jun 21 2021 %Y A121260 Cf. A121229. %K A121260 easy,nonn %O A121260 1,5 %A A121260 _Giovanni Teofilatto_, Aug 23 2006 %E A121260 Offset corrected. - _R. J. Mathar_, Jun 20 2021