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