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A124918
a(n) = least integer k >= 0 such that n = floor((5^j)/(3^k)) for some integer j >= 0.
2
0, 2, 9, 3, 0, 10, 4, 1, 17, 14, 8, 5, 2, 21, 18, 37, 15, 12, 9, 28, 6, 25, 3, 22, 0, 19, 38, 16, 35, 13, 54, 32, 10, 29, 7, 48, 26, 4, 45, 23, 1, 42, 20, 61, 39, 80, 17, 58, 36, 77, 14, 55, 33, 74, 11, 52, 30, 134, 8, 49, 153, 27, 68, 5, 46, 150, 24, 65, 2, 43, 147, 21, 125, 62
OFFSET
1,2
COMMENTS
Every nonnegative integer occurs infinitely many times. The j-sequence is A124910.
LINKS
EXAMPLE
1 = floor(5^0 / 3^0),
2 = floor(5^2 / 3^2),
3 = floor(5^7 / 3^9),
4 = floor(5^3 / 3^3), ...,
so j-sequence = (0,2,7,3,...); k-sequence = (0,2,9,3,...).
MAPLE
N:= 100: # for a(1) .. a(N)
V:=Vector(N, -1): count:= 0:
for j from 0 while count < N do
x:= 5^j;
k0:= max(0, floor(log[3](x/N)));
x:= x/3^(k0-1);
for k from k0 do
x:= x/3;
if x < 1 then break fi;
m:= floor(x);
if m <= N and V[m] = -1 then V[m]:= k; count:= count+1 fi
od od:
convert(V, list); # Robert Israel, Mar 08 2024
CROSSREFS
Cf. A124910.
Sequence in context: A276048 A339203 A179451 * A348763 A011240 A021345
KEYWORD
nonn
AUTHOR
Clark Kimberling, Nov 13 2006
STATUS
approved