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A081170
Triangle in which n-th row gives trajectory of n (including n itself) under the map x -> x/2 if x is even, x -> x-3 if x is odd, stopping when reach 0 or 1.
0
3, 0, 4, 2, 1, 5, 2, 1, 6, 3, 0, 7, 4, 2, 1, 8, 4, 2, 1, 9, 6, 3, 0, 10, 5, 2, 1, 11, 8, 4, 2, 1, 12, 6, 3, 0, 13, 10, 5, 2, 1, 14, 7, 4, 2, 1, 15, 12, 6, 3, 0, 16, 8, 4, 2, 1, 17, 14, 7, 4, 2, 1, 18, 9, 6, 3, 0, 19, 16, 8, 4, 2, 1, 20, 10, 5, 2, 1, 21, 18, 9, 6, 3, 0, 22, 11, 8, 4, 2, 1, 23, 20, 10, 5, 2
OFFSET
3,1
PROG
(PARI) xn1m3(n) = { for(x=3, n, x1=x; print1(x1" "); while(x1>1, if(x1%2==0, x1/=2, x1=x1-3); print1(x1" "); ) ) }
CROSSREFS
Cf. A080825.
Sequence in context: A131486 A127445 A324025 * A201291 A272192 A077150
KEYWORD
easy,nonn,tabf
AUTHOR
Cino Hilliard, Apr 16 2003
STATUS
approved