0,2

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

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

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.

Sequence in context: A123108 A008619 A110654 * A157271 A025162 A248180

Adjacent sequences: A109725 A109726 A109727 * A109729 A109730 A109731

base,easy,nonn

Eric Angelini, Aug 09 2005; revised Aug 25 2005

approved