|
|
|
|
0, 0, 1, 0, 1, 2, 1, 2, 3, 1, 2, 3, 2, 3, 4, 3, 4, 5, 3, 4, 5, 4, 5, 6, 5, 6, 7, 4, 5, 6, 5, 6, 7, 6, 7, 8, 6, 7, 8, 7, 8, 9, 8, 9, 10, 8, 9, 10, 9, 10, 11, 10, 11, 12, 9, 10, 11, 10, 11, 12, 11, 12, 13, 11, 12, 13, 12, 13, 14, 13, 14, 15, 13, 14, 15, 14, 15, 16
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,6
|
|
COMMENTS
|
Using the definition of A133579 this amounts to a(n) = a(n-1)-valuation_3(n) if n=3k, and a(n) = a(n-1)+1 else. - M. F. Hasler, Feb 15 2015
|
|
LINKS
|
|
|
EXAMPLE
|
a(18)=a(17)-2 because 18=3^2, a(81)=a(80)-4 because 81=3^4.
|
|
MATHEMATICA
|
nxt[{n_, a_}] := {n + 1, If[CoprimeQ[a, n + 1], 3 a, a/GCD[a, n + 1]]}; Log[3, #]&/@Join[{1}, Transpose[NestList[nxt, {1, 1}, 80]][[2]]] (* Harvey P. Dale, Feb 14 2015 *)
|
|
PROG
|
(PARI) a=-1; A253092=vector(1000, n, a+=if(n%3, 1, -valuation(n, 3))) \\ M. F. Hasler, Feb 15 2015
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|