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 A098972 #13 Jul 13 2023 02:03:01 %S A098972 1,5,13,25,41,41,89,89,121,157,157,157,301,301,301,301,365,365,581, %T A098972 581,581,581,581,581,965,965,965,1073,1073,1073,1073,1073,1201,1201, %U A098972 1201,1201,2065,2065,2065,2065,2065,2065,2065,2065,2065,2065,2065,2065,3025 %N A098972 a(0) = 1; for n > 0, a(n) = 2*a(floor(n/2)) + 3*a(floor(n/3)). %C A098972 a(n) > a(n-1) iff n is a 3-smooth number. %H A098972 Amiram Eldar, <a href="/A098972/b098972.txt">Table of n, a(n) for n = 0..10000</a> %F A098972 sign(a(n+1)-a(n)) = A065333(n+1). %t A098972 a[0] = 1; a[n_] := a[n] = 2*a[Floor[n/2]] + 3*a[Floor[n/3]]; Array[a, 50, 0] (* _Amiram Eldar_, Jul 13 2023 *) %o A098972 (PARI) a(n)=if(n<1,1,a(floor(n/2))*2+3*a(floor(n/3))) %Y A098972 Cf. A003586, A007731, A065333. %K A098972 nonn %O A098972 0,2 %A A098972 _Benoit Cloitre_, Oct 23 2004