Characteristic function of numbers that are not multiples of 9.
0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1
1 seqfan posts
Wed Feb 16 21:21:33 CET 2011 [seqfan] Re: multiplicative set-like sequences