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 A291555 #36 Aug 31 2017 06:27:10 %S A291555 0,1,4,15,40,57,76,108,146,194,258,336,447,544,663,807,970,1132,1333, %T A291555 1567 %N A291555 Number of even numbers less than 10^n that contain their greatest odd factor as a substring. %C A291555 The number of terms of A291460 less than 10^n. %C A291555 2^10*x = 1024*x contains x for all x from 1 to 41. Therefore, most of the terms in A291460 less than 10^5 are of the form 1024*x for odd x from 1 to 41. %e A291555 There are 4 numbers in A291460 less than 10^3 = 1000 (16, 128, 384, 512). Therefore, a(3) = 4. %Y A291555 Cf. A000265, A291460. %K A291555 nonn,base,more %O A291555 1,3 %A A291555 _Bobby Jacobs_ and _Robert G. Wilson v_, Aug 26 2017 %E A291555 a(14)-a(20) from _Giovanni Resta_, Aug 31 2017