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A098972 a(0)=1; for n>0, a(n)=2*a(floor(n/2))+3*a(floor(n/3)). 0
1, 5, 13, 25, 41, 41, 89, 89, 121, 157, 157, 157, 301, 301, 301, 301, 365, 365, 581, 581, 581, 581, 581, 581, 965, 965, 965, 1073, 1073, 1073, 1073, 1073, 1201, 1201, 1201, 1201, 2065, 2065, 2065, 2065, 2065, 2065, 2065, 2065, 2065, 2065, 2065, 2065, 3025 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

a(n)>a(n-1) iff n is a 3-smooth number.

LINKS

Table of n, a(n) for n=0..48.

FORMULA

sign(a(n+1)-a(n))=A065333(n+1)

PROG

(PARI) a(n)=if(n<1, 1, a(floor(n/2))*2+3*a(floor(n/3)))

CROSSREFS

Cf. A003586, A007731.

Sequence in context: A194811 A112558 A248160 * A081961 A096891 A001844

Adjacent sequences:  A098969 A098970 A098971 * A098973 A098974 A098975

KEYWORD

nonn

AUTHOR

Benoit Cloitre, Oct 23 2004

STATUS

approved

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Last modified December 7 21:06 EST 2016. Contains 278895 sequences.