login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A109751
A self-describing sequence: there are a(n) even digits and a(n) odd digits in the interval ]0;a(n)+1[.
0
10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 12, 12, 14, 14, 16, 16, 18, 18, 21, 21, 21, 23, 23, 25, 25, 27, 27, 29, 29, 30, 32, 32, 34, 34, 36, 36, 38, 38, 41, 41, 41, 43, 43, 45, 45, 47, 47, 49, 49, 50, 52, 52, 54, 54, 56, 56, 58, 58, 61, 61, 61, 63, 63, 65, 65, 67, 67, 69, 69
OFFSET
1,1
EXAMPLE
Pick the first "10" of the sequence; there are 10 even digits and 10 odd digits in the interval ]0;11[ --> 10 times "0" and 10 times "1".
Take "30"; there are 30 even digits and 30 odd digits in the interval ]0;31[, etc.
CROSSREFS
Sequence in context: A163139 A269352 A010692 * A160941 A070565 A376257
KEYWORD
base,easy,nonn
AUTHOR
Eric Angelini, Aug 11 2005
STATUS
approved