A098842 Number of n-digit Fibonacci numbers.

7, 5, 5, 4, 5, 5, 5, 4, 5, 5, 5, 5, 4, 5, 5, 5, 5, 4, 5, 5, 5, 4, 5, 5, 5, 5, 4, 5, 5, 5, 5, 4, 5, 5, 5, 4, 5, 5, 5, 5, 4, 5, 5, 5, 4, 5, 5, 5, 5, 4, 5, 5, 5, 5, 4, 5, 5, 5, 4, 5, 5, 5, 5, 4, 5, 5, 5, 5, 4, 5, 5, 5, 4, 5, 5, 5, 5, 4, 5, 5, 5, 5, 4, 5, 5, 5, 4, 5, 5, 5, 5, 4, 5, 5, 5, 5, 4, 5, 5, 5, 4, 5, 5, 5, 5

Offset

1,1

Comments

a(1)=7 because the Fibonacci numbers having one digit are the first seven; then the next five have two digits, so a(2)=5.

Links

Reinhard Zumkeller, Table of n, a(n) for n = 1..1000

Ron Knott, The Fibonacci Numbers.

Ron Knott, [Number of digits in Fib(i)] : Calculator.

Mathematica

Join[{7}, Rest[Length[#]&/@Split[IntegerLength[Fibonacci[Range[510]]]]]] (* Harvey P. Dale, Jul 19 2020 *)

Prog

(Haskell)
a098842 n = a098842_list !! (n-1)
a098842_list = map length $ group a060384_list
-- Reinhard Zumkeller, Mar 09 2013

Crossrefs

Essentially the same as A050815, which is the main entry for this sequence. Cf. A000045, A060384.

Sequence in context: A138313 A138312 A152115 * A173166 A070273 A158244

Adjacent sequences: A098839 A098840 A098841 * A098843 A098844 A098845

Keyword

base,easy,nonn

Author

Alex Vinokur (alexvn(AT)barak-online.net), Nov 03 2004

Extensions

Corrected by Alexandre Wajnberg, Mar 28 2005

Status

approved