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a(n)>a(n-1) iff n is a 3-smooth number.
Table of n, a(n) for n=0..48.
(PARI) a(n)=if(n<1, 1, a(floor(n/2))*2+3*a(floor(n/3)))
Cf. A003586, A007731.
Sequence in context: A194811 A112558 A248160 * A081961 A096891 A001844
Adjacent sequences: A098969 A098970 A098971 * A098973 A098974 A098975
Benoit Cloitre, Oct 23 2004