A368010 Ordinal transform of the leading digit of the factorial numbers.

1, 2, 1, 1, 2, 3, 1, 1, 1, 1, 2, 3, 2, 2, 1, 4, 3, 4, 3, 5, 4, 2, 6, 5, 4, 7, 3, 8, 5, 2, 6, 3, 7, 4, 8, 9, 6, 10, 3, 9, 5, 7, 11, 5, 10, 12, 4, 11, 13, 6, 8, 14, 6, 4, 12, 15, 2, 5, 13, 16, 7, 5, 9, 17, 18, 8, 6, 10, 14, 19, 20, 9, 7, 6, 11, 15, 21, 22, 23, 10

Offset

0,2

Comments

n is the a(n)-th nonnegative integer producing value A008905(n).

Links

Alois P. Heinz, Table of n, a(n) for n = 0..20000

Formula

Ordinal transform of A008905.

a(n) = |{ j in {0..n} : A008905(j) = A008905(n) }|.

Example

a(11) = 3 because 11! = 39916800 is the third factorial with leading digit 3 after 9! = 362880 and 10! = 3628800.  A008905(k) = 3 for k = 9, 10, 11, ... .

Crossrefs

Cf. A000142, A008905, A367799.

Sequence in context: A144790 A090996 A309736 * A237453 A265754 A089309

Adjacent sequences: A368007 A368008 A368009 * A368011 A368012 A368013

Keyword

nonn,look,base

Author

Alois P. Heinz, Dec 07 2023

Status

approved