login
A177246
Fibonacci numbers whose decimal expansion does not contain any digit 4.
5
1, 1, 2, 3, 5, 8, 13, 21, 55, 89, 233, 377, 610, 987, 1597, 6765, 17711, 28657, 75025, 121393, 317811, 2178309, 5702887, 39088169, 1836311903, 2971215073, 12586269025, 32951280099, 53316291173, 86267571272, 591286729879
OFFSET
1,3
COMMENTS
Probability that Fib(n) contains no 4's goes to zero as n grows to infinity. I suppose that the maximum number is Fib(114) having 24 digits, none of them being a "4".
LINKS
Robert Israel, Table of n, a(n) for n = 1..41 (conjectured to be complete)
EXAMPLE
a(9)=55 is the 9th Fibonacci having no digit 4's.
MAPLE
remove(t -> has(convert(t, base, 10), 4), map(combinat:-fibonacci, [$1..1000])); # Robert Israel, Dec 13 2018
MATHEMATICA
Select[Fibonacci@Range@114, !MemberQ[IntegerDigits[#], 4] &] (* Amiram Eldar, Dec 13 2018 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Carmine Suriano, May 06 2010
STATUS
approved