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A109728 A self-describing sequence. 0
1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10, 12, 12, 14, 14, 16, 16, 18, 18, 20, 21, 21, 23, 23, 25, 25, 27, 27, 29, 29, 31, 32, 32, 34, 34, 36, 36, 38, 38, 40, 41, 41, 43, 43, 45, 45, 47, 47, 49, 49, 51, 52, 52, 54, 54, 56, 56, 58, 58, 60, 61, 61, 63, 63 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..71.

FORMULA

There are a(n) digits having the same parity as a(n) in the interval ]0;a(n)+1[.

EXAMPLE

Pick the first "4" in the sequence; "4" is even; there are 4 even digits in the interval ]0;5[ -> 2,2,4 and 4.

Take "21", which is odd; there are 21 odd digits in the interval ]0;22[ -> 1 3 3 5 5 7 7 9 9 1 1 1 1 1 1 1 1 1 1 1 and 1 = 21.

CROSSREFS

Sequence in context: A123108 A008619 A110654 * A157271 A025162 A248180

Adjacent sequences:  A109725 A109726 A109727 * A109729 A109730 A109731

KEYWORD

base,easy,nonn

AUTHOR

Eric Angelini, Aug 09 2005; revised Aug 25 2005

STATUS

approved

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Last modified May 27 07:44 EDT 2019. Contains 323599 sequences. (Running on oeis4.)