A332701 - OEIS

A332701

Lexicographically earliest sequence of distinct positive terms such that the digitsum of a(n) is the length of a(n+1).

1, 2, 10, 3, 100, 4, 1000, 5, 10000, 6, 100000, 7, 1000000, 8, 10000000, 9, 100000001, 11, 12, 101, 13, 1001, 14, 10001, 15, 100001, 16, 1000001, 17, 10000001, 18, 100000002, 102, 103, 1002, 104, 10002, 105, 100002, 106, 1000002, 107, 10000002, 108, 100000003

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OFFSET

1,2

COMMENTS

The digitsum (sometimes called digsum) of an integer is the sum of its digits. The digitsum of 54321 is 5+4+3+2+1 = 15 (see A007953).

Among the first 10000 terms the largest value is 10000000000000000000000003. For 100000 terms it is 1000000000000000000000000000000004. - Lars Blomberg, Feb 22 2020

LINKS

Lars Blomberg, Table of n, a(n) for n = 1..10000

EXAMPLE

a(1) = 1 with digitsum 1 and a(2) = 2 has 1 digit;

a(2) = 2 with digitsum 2 and a(3) = 10 has 2 digits;

a(3) = 10 with digitsum 1 and a(4) = 3 has 1 digit;

a(4) = 3 with digitsum 3 and a(5) = 100 has 3 digits;

a(5) = 100 with digitsum 1 and a(6) = 4 has 1 digits;

a(6) = 4 with digitsum 4 and a(7) = 1000 has 4 digits; etc.

CROSSREFS

A007953 (Digital sum (i.e., sum of digits) of n; also called digsum(n)).

Sequence in context: A276486 A341363 A234932 * A342158 A344544 A364262

Adjacent sequences: A332698 A332699 A332700 * A332702 A332703 A332704

KEYWORD

base,nonn

AUTHOR

Eric Angelini and Lars Blomberg, Feb 20 2020

STATUS

approved