

A103756


Number of contiguous digits i in the counting numbers, for i=2.


0



1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 2, 2, 5, 2, 2, 2, 2, 2, 2, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1
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OFFSET

1,5


COMMENTS

Write the natural numbers as an infinite sequence of digits, starting at the left; and count the digits of each group of "2"'s you encounter (the smallest "groups" have one "2").


LINKS

Table of n, a(n) for n=1..105.


EXAMPLE

a(1)=1: the first "2" of the counting numbers, isolated.
a(2)=1: the second "2", second digit of number 12, isolated.
a(3)=1 the first digit of number 20, isolated.
a(4)=1: the first digit of number 21, isolated.
a(5)=3: two "2"'s of 22 followed by one "2" of 23 = three "2"'s, the next group of "2"'s.


CROSSREFS

Sequence in context: A175739 A260196 A094404 * A103755 A326538 A333844
Adjacent sequences: A103753 A103754 A103755 * A103757 A103758 A103759


KEYWORD

nonn,base


AUTHOR

Alexandre Wajnberg, Mar 28 2005


STATUS

approved



