|
|
A003965
|
|
Fully multiplicative with a(prime(k)) = Fibonacci(k+2).
|
|
8
|
|
|
1, 2, 3, 4, 5, 6, 8, 8, 9, 10, 13, 12, 21, 16, 15, 16, 34, 18, 55, 20, 24, 26, 89, 24, 25, 42, 27, 32, 144, 30, 233, 32, 39, 68, 40, 36, 377, 110, 63, 40, 610, 48, 987, 52, 45, 178, 1597, 48, 64, 50, 102, 84, 2584, 54, 65, 64, 165, 288, 4181, 60, 6765, 466, 72, 64, 105, 78, 10946
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
COMMENTS
|
Numbers k such that a(k) = k are exactly 5-smooth numbers (A051037). - Ivan Neretin, Aug 30 2015
|
|
LINKS
|
|
|
FORMULA
|
If n = Product p(k)^e(k) then a(n) = Product Fibonacci(k+2)^e(k).
|
|
MATHEMATICA
|
Table[Times @@ (Fibonacci[PrimePi[#[[1]]] + 2]^#[[2]] & /@ FactorInteger[n]), {n, 67}] (* Ivan Neretin, Aug 30 2015 *)
|
|
PROG
|
(PARI) a(n) = my(f=factor(n)); for (k=1, #f~, f[k, 1] = fibonacci(primepi(f[k, 1])+2)); factorback(f); \\ Michel Marcus, Jan 14 2021
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn,mult
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|