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A113196
a(n) = F(n)/Product_{p=primes} F(p^(m_{n,p})), where p^(m_{n,p}) is highest power of p dividing n, m= nonnegative integer and F(k) is the k-th Fibonacci number.
1
1, 1, 1, 1, 1, 4, 1, 1, 1, 11, 1, 24, 1, 29, 61, 1, 1, 76, 1, 451, 421, 199, 1, 1104, 1, 521, 1, 8149, 1, 83204, 1, 1, 19801, 3571, 141961, 146376, 1, 9349, 135721, 974611, 1, 10304396, 1, 2626999, 6675901, 64079, 1, 2435424, 1, 167761, 6376021, 47140601, 1
OFFSET
1,6
COMMENTS
Every term of sequence is an integer.
FORMULA
a(n) = F(n)/A113195(n).
EXAMPLE
12 = 2^2 * 3^1, so a(12) = F(12)/ (F(2^2) * F(3^1)) = 144/(3*2) = 24.
MAPLE
a:= n-> (F-> F(n)/mul(F(i[1]^i[2]), i=ifactors(n)[2]))(k->(<<0|1>, <1|1>>^k)[1, 2]):
seq(a(n), n=1..53); # Alois P. Heinz, Feb 02 2025
MATHEMATICA
b[t_]:=Fibonacci[First[t]^Last[t]] a[n_]:=Fibonacci[n]/Apply[Times, Map[b, FactorInteger[n]]] (Peuha)
PROG
(PARI) { for(n=1, 100, f=factor(n); p=1; for(i=1, matsize(f)[1], p*=fibonacci(f[i, 1]^f[i, 2])); print1(fibonacci(n)/p, ", ")) } \\ Lambert Klasen, Oct 26 2005
CROSSREFS
Sequence in context: A222639 A184729 A127707 * A037291 A222317 A063851
KEYWORD
nonn
AUTHOR
Leroy Quet, Oct 17 2005
EXTENSIONS
More terms from Esa Peuha (esa.peuha(AT)helsinki.fi) and Lambert Klasen (lambert.klasen(AT)gmx.net), Oct 26 2005
STATUS
approved