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A082561
a(1)=1, a(n)=3*a(n-1) if n is not a multiple of 3, or a(n)=a(n/3)+1 if n is a multiple of 3.
0
1, 3, 2, 6, 18, 4, 12, 36, 3, 9, 27, 7, 21, 63, 19, 57, 171, 5, 15, 45, 13, 39, 117, 37, 111, 333, 4, 12, 36, 10, 30, 90, 28, 84, 252, 8, 24, 72, 22, 66, 198, 64, 192, 576, 20, 60, 180, 58, 174, 522, 172, 516, 1548, 6, 18, 54, 16, 48, 144, 46, 138, 414, 14, 42, 126, 40, 120
OFFSET
1,2
COMMENTS
b(1)=1, b(n)=3*b(n/3) if n is a multiple of 3, or b(n)=b(n-1)+1 if n is not a multiple of 3 produces the sequence 1, 2, 3, 4, ...
PROG
(PARI) a(n)=if(n<2, 1, if(n%3, 3*a(n-1), 1+a(n/3)))
CROSSREFS
Sequence in context: A285457 A007812 A276225 * A268642 A110768 A140230
KEYWORD
nonn
AUTHOR
Benoit Cloitre, May 04 2003
STATUS
approved