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A103755
Number of contiguous digits i in the counting numbers, for i=1.
0
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, 2, 5, 2, 2, 2, 2, 2, 2, 2, 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, 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
OFFSET
1,3
COMMENTS
Write the natural numbers as an infinite sequence of digits, starting at the left; and count the digits of each group of "1"'s you encounter (the smallest "groups" have one "1").
EXAMPLE
a(1)=1: the first "1" of the counting numbers, isolated.
a(2)=1: the second "1", first digit of number 10, isolated.
a(3)=3 two "1"'s of 11 and one "1" of 12 = three "1"'s, the next group of "1"'s.
CROSSREFS
Sequence in context: A094404 A361129 A103756 * A355818 A326538 A333844
KEYWORD
base,easy,nonn
AUTHOR
Alexandre Wajnberg, Mar 28 2005
STATUS
approved