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A155817 Sequence having the property that a(n) is the sum of the first a(n) digits of the sequence 2
1, 10, 2, 4, 100, 101, 11, 12, 13, 14, 30, 1000, 10000, 40, 41, 100000, 102, 43, 60, 110, 1000000, 1001, 61, 80, 111, 100000000000, 90, 10000000, 103, 104, 10001, 1110, 112, 201, 108, 91, 95, 160, 161, 100000000000000000000000000000000000, 170, 1000001 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

From an idea of Eric Angelini. The condition of strict monotonicity is dropped with respect to A154328.

LINKS

Jon Schoenfield, Table of n, a(n) for n = 1..1000

EXAMPLE

We start with a(1)=1. The next term a(2) cannot be 2,...,9 because the sum of these digits would be larger: the least possibility not leading to a contradiction is a(2)=10. Then we can go on with a(3)=2 because the sum of the first two digits, 1=a(1) and 1 from 10=a(2), is equal to 2. Then a(4)=4 because sum of the first 4 digits, 1+1+0+2, is equal to 4.

CROSSREFS

Cf. A154328

Sequence in context: A169851 A161995 A069036 * A037922 A111287 A255668

Adjacent sequences:  A155814 A155815 A155816 * A155818 A155819 A155820

KEYWORD

nonn,base

AUTHOR

Paolo P. Lava, Jan 28 2009

EXTENSIONS

Sequence corrected and extended by N. J. A. Sloane, Aug 31 2009, using terms from the b-file.

STATUS

approved

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Last modified March 28 05:07 EDT 2017. Contains 284182 sequences.