OFFSET
1,2
COMMENTS
The position 1 corresponds to the most significant bit.
LINKS
Paul Tek, Table of n, a(n) for n = 1..3321
Paul Tek, PARI program for this sequence
FORMULA
a(n) = Sum_{a(i) <= n+1} 2^(n+1-a(i)), for any n>1, with a(1)=1.
EXAMPLE
1 has a 1 at position 1, and no 0's, hence 1 belongs to the sequence.
2 has a 0 at position 2, hence 2 cannot belong to the sequence.
3 has a 1 at position 2, as 2 cannot belong to the sequence, 3 cannot either.
4 has a 1 at position 1, and 0's at positions 2 and 3, hence 4 belongs to the sequence.
9 has 1's at positions 1 and 4, and 0's at positions 2 and 3, hence 9 belongs to the sequence.
PROG
(PARI) See Link section.
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Paul Tek, Sep 12 2013
STATUS
approved